Chapter III:
Europe Versus the Pacific

The second rule is to concentrate your power as much as possible against that section where the chief blows are to be delivered and to incur disadvantages elsewhere.


Since 1938, when the last revision of ORANGE was completed, American military strategists had made every effort to bring their plans into line with the rapidly changing situation in Europe and Asia. The world was dividing into two armed camps. On one side were Germany and Italy, associated with Japan by the Anti-Comintern Pact. For three years, these powers had been pursuing their aggressive policies in the Rhineland, Ethiopia, Austria, and China. On the other side were the democratic powers, Great Britain and France. Still suffering from the prolonged economic crisis of the early 1930's and weakened by domestic conflicts, these two had remained passive in the face of Axis threats and sought to avert armed conflict by a policy of appeasement. While such hopes did not seem entirely without foundation at the time, American leaders could no longer ignore the possibility of becoming involved in a two-ocean war.

The 1938 revision of ORANGE, with its emphasis on flexibility, represented an effort to bring strategy into line with the international situation. The Navy's single-minded insistence on an advance into the western Pacific was still reflected .in the plan, but it was modified by an increasing awareness of the uncertainties of a world threatened by the rising tide of Axis aggression. The Army, with its concern for the defense of the United States, was shifting away from the Pacific orientation that had dominated strategic planning since World War I and was turning anxious eyes toward Europe. A RED or a RED-ORANGE war was no longer within the realm of probability, but the Atlantic area occupied more and more of the attention of the strategists after 1938.1


Strategic Adjustment, 1938-1940

Though it was the Army planners who seemed most aware of the danger from Europe, it was the Navy that made the first move to strengthen America's Atlantic defenses. In December 1937, shortly after the Panay incident, the Director of the Navy War Plans Division, Capt. Royal E. Ingersoll, was sent to London to discuss informally with the British Admiralty the new construction programs of the two navies and the conditions of U.S.-British naval co-operation in the event both nations were involved in a war against Japan. During the course of these discussions, the possibility of a German war inevitably arose. The British viewed this possibility with real concern, for the Germans could be expected to attack British trade routes in the Atlantic. Should Italy join Germany, the prospects were even more alarming. The French, if they entered the war, would hold the western Mediterranean, but the British would still have to place the bulk of their forces in the Atlantic. They would have little, therefore, to send to the Far East. Here the United States could perform a valuable service in the common cause by taking up the slack in the Far East in return for the security the Royal Navy would provide in the Atlantic. Even if the United States became involved in the European conflict, Great Britain could still be relied upon to man the Atlantic barrier so long as the U.S. Fleet assumed responsibility for the Pacific. It is perhaps for this reason that the Navy members of the Joint Planning Committee, in their discussions over ORANGE in 1938, seemed less concerned about the Atlantic and more interested in the Pacific than the Army planners.2

Events in Europe in the fall of 1938 fully justified the concern of American policy makers and planners, and the Munich crisis in September of that year provided the impetus to a comprehensive review of American strategy. Taking the lead from the public statements of President Roosevelt and Secretary of State Hull, the Joint Board directed its planning committee in November to make a study of the course the United States should follow if German and Italian aggression in Europe and Japanese expansion in the Far East should threaten American security and interests in both the Atlantic and Pacific simultaneously.3

Here, for the first time, was a specific directive to the planners to study, within the context of the current international situation, the problems presented by a two-ocean war in which the United States, acting in concert with allies, would be opposed by a coalition. These problems had been studied before in the ORANGE-RED plans, but under entirely different assumptions and in a completely different situation. They had been considered briefly and tangentially also in the latest revision of ORANGE with its provision for a position of readiness and co-operation with allies. The informal naval conversations in London in January 1938 were a clear recognition of the possibility of such a war and the first step toward the intimate military collaboration that marked the Anglo-


American relationship during World War II.

For almost six months the planners of the Joint Board considered the problem presented by simultaneous Axis aggression in the Atlantic and Pacific areas and finally in April 1939 submitted their report. In it they reviewed the world situation, estimated the likelihood of war, calculated the probable objectives of the Axis in Europe and Japan in the Far East, discussed the effects of concerted action by these powers on the United States, and analyzed the strategic problems involved in the various situations that might result from such action. So comprehensive was the report, such a model of strategic analysis, that it was characterized by the Joint Board as "a monument" to its planning committee and became the basis for much of the strategic planning before Pearl Harbor.4

In their effort to arrive at a sound military strategy for the United States, the joint planners examined the various contingencies that might arise as a result of Axis aggression. Based on this examination, they concluded:

  1. Germany and Italy would take overt action in the Western Hemisphere only if Great Britain and France remained neutral or were defeated.

  2. Japan would continue to expand into China and Southeast Asia at the expense of Great Britain and the United States, by peaceful means if possible but by force if necessary.

  3. The three Axis Powers would act together whenever the international situation seemed favorable. If other countries, including the United States, reacted promptly and vigorously to such action then a general war might well follow.

The reaction of the United States to these or any other situations that might arise, the planners pointed out, would depend in large measure on the forces available and the extent to which American interests were involved. In the event of a threat in both oceans simultaneously, the United States, they maintained, should assume the defensive in the Pacific, retaining adequate forces based on Hawaii to guard the strategic triangle. Arguing further in a manner reminiscent of RED-ORANGE planning, the strategists of the Joint Board declared that priority in a two-ocean war must go first to the defense of vital positions in the Western Hemisphere -- the Panama Canal and the Caribbean area. From bases in that region, the U.S. Fleet could operate in either ocean as the situation demanded, but its primary obligation must always be to control the Atlantic approaches to the Western Hemisphere, especially to the south where the continent was most exposed. This task would not be difficult if Great Britain and France actively opposed Axis aggression, but if they did not the security of the South Atlantic would become the major concern of U.S. forces. In this situation, the active co-operation of the Latin American states was indispensable.

In their studies the planners also considered the possibility of a war with Japan alone. The United States would have to expect to lose all its possessions west of 180 degrees early in such a war, which, the planners prophetically pointed out, might well begin with a Japanese effort "to damage major fleet units without


warning," or a surprise attempt "to block the fleet in Pearl Harbor." It would be necessary, then, for American forces to fight their way back across the Pacific in a series of amphibious operations using one of four routes: (1) the Aleutians; (2) Pearl Harbor-Midway-Luzon; (3) the Marshalls-Carolines-Marianas-Yap-Peleliu; and (4) Samoa-New Guinea-Mindanao. The planners favored the second and third routes and thought that a combination of the two would have to be used. The garrisons in Hawaii, Alaska, and Panama were to be reinforced, but not the Philippines, apparently on the assumption that their loss was certain. The planners were astute enough to recognize, however, that "emotionalized opinion rather than . . . a reasoned adjustment of operations to the means at hand" might ultimately dictate the choice of battleground.

American military forces in 1939 seemed sufficiently strong to accomplish the minimum tasks required under the strategic concept proposed by the planners -- defense of U.S. vital interests in the Western Hemisphere and in the Atlantic area. After hostilities began, American forces could be strengthened sufficiently to defeat the enemy operating in the Atlantic, even without the aid of Great Britain and France. If, at the same time, the United States maintained adequate defensive forces in the Pacific, Japan could probably be restricted to the western Pacific. It was even possible, in such a situation, that the Japanese leaders might prefer peace with the United States, hoping thereby to reap a profit from the war without cost to themselves. If, on the other hand, Japan initiated hostilities and the United States adopted a position of readiness but refrained from an advance to the western Pacific, the European Axis would probably not undertake any aggressive adventures in the Western Hemisphere. Thus, on all accounts, the planners held that a defensive strategy in the Pacific was preferable to any other course.

On the basis of their study the joint planners recommended that a series of war plans be prepared, each of them to be applicable to a different situation. Priority in these plans, they held, must be given to the defense of the United States, and this would require safeguarding the security of the Western Hemisphere. To hold firm to these objectives would be no easy task, the planners recognized. Not only must strategy be linked to policy, but it must also take cognizance of such intangibles as tradition, the spirit of the nation, and "emotionalized public opinion."

The pioneering study by the joint planners in 1939 raised sharply and dramatically the question of American policy in the event of concerted aggression by Germany, Italy, and Japan. By focusing on the threat to the Caribbean and South America, the planners challenged strongly the long-standing orientation of American strategy toward the Pacific and gave weight to the Army's arguments against offensive operations in the western Pacific.

The planners raised another issue that needed to be resolved before the course of national policy could be charted. All the color plans had been based on the assumption the United States would act alone. Was this assumption valid in terms of the international situation and in the face of a threatening Axis coalition? Should the strategists in drawing up their plans therefore assume that the


United States would have allies? And if so, who would they be and what would the United States be expected to do for them and they for this nation? Like the Atlantic vs. Pacific issue, this question of allies involved political matters and would have to be resolved by the President himself.

It was perhaps as well that no firm answers were forthcoming in the spring of 1939, for the course of events was still far from clear. The planners recognized this when they proposed that alternative plans be prepared to meet different situations in which the United States would have to meet the combined threat of Germany, Italy, and Japan. The Joint Board, in approving the work of the planners, accepted this recommendation and in June 1939 laid down the guide lines for the development of these war plans, aptly designated RAINBOW to distinguish them from the color plans.5

There were ultimately five RAINBOW plans in all, each of them based on a different situation. The objective of all was the same -- to defend the United States and the Western Hemisphere from Axis aggression and penetration, overt or concealed. In each of the plans the planners "set forth the specific co-operation that should be sought from allied or neutral Democratic Powers, with respect to specific Theaters of Operations to render our efforts fully effective." Common to all of the plans was the assumption that the United States would face a coalition rather than a single power.

The five specific situations forming the basis of the five RAINBOW plans were defined by the Joint Board as follows:

RAINBOW 1 assumed the United States to be at war without major allies. United States forces would act jointly to prevent the violation of the Monroe Doctrine by protecting the territory of the Western Hemisphere north of latitude 10' south, from which the vital tasks of the United States might be threatened. The joint tasks of the Army and Navy included protection of the United States, its possessions and its seaborne trade. A strategic defensive was to be maintained in the Pacific, from behind the line Alaska-Hawaii-Panama, until developments for offensive action against Japan.

RAINBOW 2 assumed that the United States, Great Britain, and France would be acting in concert, with limited participation of U.S. forces in continental Europe and in the Atlantic. The United States could, therefore, undertake immediate offensive operations across the Pacific to sustain the interests of democratic powers by the defeat of enemy forces.

RAINBOW 3 assumed the United States to be at war without major allies. Hemisphere defense was to be assured, as in RAINBOW 1, but with early projection of U.S. forces from Hawaii into the western Pacific.

RAINBOW 4 assumed the United States to be at war without major allies, employing its forces in defense of the whole of the Western Hemisphere, but also with provision for United States Army forces to be sent to the southern part of South America, and to be used in joint operations in eastern Atlantic areas. A strategic defensive, as in RAINBOW 1, was to be maintained in the Pacific until the situation in the Atlantic permitted transfer of major naval forces for an offensive against Japan.

RAINBOW 5 assumed the United States, Great Britain, and France to be acting in


concert; hemisphere defense was to be assured as in RAINBOW 1, with early projection of U.S. forces to the eastern Atlantic, and to either or both the African and European continents; offensive operations were to be conducted, in concert with British and allied forces, to effect the defeat of Germany and Italy. A strategic defensive was to be maintained in the Pacific until success against European Axis Powers permitted transfer of major forces to the Pacific for an offensive against Japan.6

Of the five plans, RAINBOW 1 was basic, though most limited. Providing for the defense of the Western Hemisphere from the bulge of Brazil to Greenland and as far west as Midway in the Pacific, it established the necessary conditions that had to be met before any of the other plans could be executed. RAINBOWs 2 and 3 called for offensive operations into the western Pacific, the former on the assumption that Great Britain and France would be allies, and the latter that they would not. In this respect, RAINBOW 3 established virtually the same conditions as the ORANGE plan. RAINBOW 4 also assumed that Great Britain and France would be neutral, presumably as a result of Axis military action, and therefore emphasized the defense of the Western Hemisphere against external aggression. Emphasis in this plan as in RAINBOW 1 was on limited action to fend off any Axis threat to the American republics. In neither RAINBOW 1 nor 4 were major U.S. forces to be sent to Europe or to the far Pacific.

The situation envisaged in RAINBOW 5 came closer to the conditions of World War II than any of the others, though these were not foreseen at the time. Like RAINBOW 2, it assumed the active collaboration of Great Britain and France. But unlike that plan, which called for the United States to make the major effort in the Pacific, RAINBOW 5 envisaged the rapid projection of American forces across the Atlantic to Africa or Europe "in order to effect the decisive defeat of Germany, Italy, or both." Clearly implied in this statement was the concept that finally emerged as the basic strategy of World War II: that in a war with the European Axis and Japan, Germany would be the major enemy and the main effort would be made in Europe to secure the decisive defeat of Germany at the earliest possible date.

The summer of 1939 was one of tense expectancy. Europe was on the verge of war and Japan showed no disposition to abandon aggression in Asia. During these months, a joint RAINBOW 1 plan, which had first priority, was completed and the two services hurriedly pushed forward completion of their own plans for hemisphere defense.7

There were important organizational changes, too, at this time. In an effort to keep in close touch with his military advisers, President Roosevelt on 5 July 1939 placed the Joint Board under his immediate "supervision and direction." Up to that time, the board, it will be recalled, had reported to the two service Secretaries, under whose authority the board functioned. It had now a broader basis, but still sent its recommendations through the Secretaries, for the President had no desire to alter existing procedures.8



This change coincided with a change in the high command. On August, Admiral Harold R. Stark was appointed Chief of Naval Operations to succeed Admiral Leahy, and a month later General George C. Marshall formally succeeded General Malin Craig as Chief of Staff of the Army after two months as Acting Chief.

The outbreak of war in Europe early in September 1939 gave a fresh urgency to RAINBOW planning. RAINBOW 2 seemed to fit the situation of the moment best and while work went forward on the development of plans, the President took measures to strengthen the nation's defenses and to keep America out of war by keeping war away from America. Immediately on the outbreak of hostilities he proclaimed the neutrality of the United States, while ordering the Army and Navy to bring their strength up to the full authorized level. On his initiative, the Foreign Ministers of the American Republics met at Panama at the end of September to proclaim their neutrality and to devise measures for their joint defense. American security zones were proclaimed in the western Atlantic and eastern Pacific, and plans made to patrol these zones to keep war away from the Americas.

Throughout the winter of 1939-1940, the period of the "phony war," the joint planners sought to develop plans to meet the RAINBOW 2 contingency. The task proved a formidable one, indeed, for the range of possibilities was wide. Moreover, each proposed course of action in the Pacific had to be co-ordinated


with that of the Allies. But without specific knowledge of the plans of their allies, the planners were faced with many uncertainties. In April 1940, therefore, they proposed that conversations should be held with the British, French, and Dutch "as soon as the diplomatic situation permits." By that time, the Army planners had prepared four drafts of a proposed RAINBOW 2 plan, on each of which the Navy had commented in detail.9

The Critical Summer of 1940

The planners were still trying to solve the problems posed by RAINBOW 2 when the nature of the war in Europe changed abruptly in the spring of 1940. Early in April, German forces invaded Denmark and Norway and by the end of the month had occupied both countries. On 10 May, the German campaign against France opened with the attack on the Netherlands and Belgium, and four days later German armor broke through the French defenses in the Ardennes. At the end of the month the British began the evacuation from Dunkerque, and on 10 June, Italy declared war. A week later, the beaten and disorganized French Government sued for peace. With France defeated and England open to attack and invasion, the threat from the Atlantic looked real indeed.

Nor was there any consolation to be found in the situation in Asia. In China, the Japanese had succeeded in occupying North China, the coastal area as far south as Canton, and the principal river and rail lines. Tokyo diplomats were speaking of a Japanese "Monroe Doctrine," and there was every indication that Japan intended to exploit the Axis victories in Europe and take over the French, British, and Dutch possessions in Asia and the Southwest Pacific. Only the United States was in a position to challenge Japan, and on 10 April 1940 the Joint Board instructed its planners to give priority to the development of plans based on RAINBOW's 2 and 3, both of which called for offensive operations in the Pacific.10 That same month, the Pacific Fleet moved into Hawaiian waters for maneuvers, and despite the protests of its commander was kept there throughout the spring as a deterrent to Japanese aggression. Finally in June, when a Soviet-Japanese pact freed Japan for further aggression to the south, the fleet was ordered to remain indefinitely in Hawaiian waters. So tense was the situation that on the 17th of the month, as a result of reports of possible attacks on Pearl Harbor or Panama Canal, General Marshall sent alerts to the Army commanders in Hawaii and Panama.11

In this crisis, American strategy underwent a critical review. Clearly the greater danger was in Europe, and RAINBOW's 2 and 3 with their orientation toward the far Pacific were scarcely applicable. The defeat of France in June and


the possibility that Great Britain might soon fall outweighed any danger that Japanese aggression could present to American security. Calling for an early decision from higher authority, the Army planners argued that since the United States could not fight everywhere -- in the Far East, Europe, Africa, and South America -- it should limit itself to a single course. Defense of the Western Hemisphere, they held, should constitute the main effort of American forces. In any case, the United States should not become involved with Japan and should concentrate on meeting the threat of Axis penetration into South America.12

The Army's concern about America's ability to meet a possible threat from an Axis-dominated Europe in which the British and French Navies might be employed against the United States was shared by the Navy. As a result, the joint planners began work on RAINBOW 4, which only a month earlier had been accorded the lowest priority, and by the end of May had completed a plan. The situation envisaged now in RAINBOW4 was a violation of the Monroe Doctrine by Germany and Italy coupled with armed aggression in Asia after the elimination of British and French forces and the termination of the war in Europe. Under these conditions, the United States was to limit itself to defense of the entire Western Hemisphere, with American forces occupying British and French bases in the western Atlantic.13

Acceptance by the Joint Board of the RAINBOW 4 plan was the beginning rather than the end of the comprehensive review of strategy precipitated by Germany's startling success in Europe. Still in doubt was the fate of Great Britain and the French Navy, and American policy depended to a very large degree on these two unknowns. Possession of the British and French Fleets would give the European Axis naval equality with the U.S. Fleet and make possible within six months, the time required to make the captured fleets operational, hostile Axis operations in the Western Hemisphere. Since considerable time would be required to mobilize, equip, and train American forces, the planners asserted that "the date of the loss of the British or French Fleets automatically sets the date of our mobilization."14

During the dramatic weeks of May and June 1940, the President met with his military advisers frequently and discussed with them every major development of the war. On 13 June, shortly before the fall of France, he called in the intelligence chiefs of the Army and Navy for an evaluation of the situation, posing a number of specific questions. This request precipitated an interim review of the various courses of action open to the United States in the light of the rapidly changing situation. As the planners saw it, there were three alternatives:

  1. To maintain a strong position in the Pacific and to avoid commitment everywhere else.


  1. To make every effort, including belligerent participation, to sustain Great Britain and France.

  2. To take whatever measures were required to prevent Axis penetration into the Western Hemisphere.15


All three possibilities had already been considered in one or another of the RAINBOW plans, but, as the planners pointed out, the essence of the problem now was time. RAINBOW 4 was the best course to follow in this situation, in their view, and the end of British or French resistance, they held, should be the signal for American mobilization.16

On the morning of 17 June, the day after the planners had submitted their report, General Marshall discussed the problem with his immediate assistants. "Are we not forced," he asked, "into a question of reframing our national policy, that is, purely defensive action in the Pacific, with a main effort on the Atlantic side? We have to be prepared," Marshall told his staff, "to meet the worst situation that may develop, that is, if we do not have the Allied fleet in the Atlantic." The time had come, he thought, to mobilize the National Guard and to discontinue shipments to England of munitions that would be needed for American mobilization. On the basis of this discussion, the Chief of the War Plans Division, Brig. Gen. George V. Strong, recommended that same day that the Chief of Staff and the Chief of Naval Operations propose to the President as the basic policy of the United States: first, a purely defensive position in the Pacific; second, no further commitments for material aid to the Allies; and third, immediate mobilization for hemisphere defense. These recommendations reflected the pessimistic and strongly conservative outlook of the Army staff at the time, a view the Army planner made no effort to conceal. His proposal, Strong stated frankly, was "a recognition of the early defeat of the Allies, an admission of our inability to furnish means in quantities sufficient to affect the situation, and an acknowledgement that we recognize the probability that we are next on the list of Axis powers. . . ."17

General Marshall and Admiral Stark approved General Strong's recommendations in principle on 18 June and directed their planners to outline the measures required "to effect an immediate


mobilization of national effort for Hemisphere Defense." The result was a comprehensive review of national policy during the latter part of June by the War and Navy Departments, the State Department, and the President. With the study of the questions proposed by Roosevelt on the 13th, this review furnished an estimate of probable war developments -- and outlined the action required for full-scale mobilization and for aid to Britain and her allies. Though never approved by the President, the conclusion of the planners nevertheless reflected his views and constituted an important milestone in the development of U.S. strategy for World War II.18

The critical point at issue in the discussions was the fate of the French Fleet and the future of Great Britain. Military leaders wished to base their plans on the worst of all possible contingencies -- that England, if not the British Empire, would be forced out of the war and that the French and British Fleets would fall to the Axis. The President, on the other hand, believed that American action should be based on the assumption that Great Britain would remain an active belligerent and that the military situation in Europe would not alter appreciably in the next six months. He did not feel, either, that aid to Britain should be cut off entirely, and countered the planner's arguments with the observation that if a small amount of aid would see the British through without seriously retarding American preparations, then that aid should be furnished. Nor was the President willing to put the armed forces on a wartime basis or to support full mobilization of manpower and industry. He agreed on the necessity for defense of the Western Hemisphere and the protective occupation of European colonial possessions as well as other strategic positions in the Caribbean area and in Central and South America, but only after consultation and negotiation with the Latin American nations concerned.

As a result of these discussions, the planners recommended that American policy be based on the following:

  1. That the British Empire would continue to exist in the fall and winter of 1940, though Great Britain itself might not remain an active combatant.

  2. That France would be occupied by German forces, and even if the French in North Africa and elsewhere continued resistance, U.S. aid would not alter substantially the French position.

  3. That U.S. participation in the war as an active belligerent could not prevent the defeat of France or of Great Britain at this time.

This estimate of the situation at the end of June, which incorporated the President's views, led the planners to recommend as the "Basis for Immediate Decisions Concerning the National Defense" a defensive in the Pacific, irrespective of the fate of the French Fleet. But if that fleet did fall into German hands, the planners recognized they would have to consider the question of whether to move the major portion of the U.S. Fleet to the Atlantic. The planners thought, too, that the further release of war materials needed for American forces would seriously weaken the United States. But they did not rule out altogether aid to Britain and stipulated, in accordance with Roosevelt's


wishes, that aid would be given "under certain circumstances."19

During the summer of 1940, American policy and strategy were shaped in large measure by President Roosevelt's conviction that Britain must be encouraged to resist and that the British Fleet must not be permitted to fall to Germany. In a real sense, therefore, American strategy was dependent upon British fortunes. Only "one force," said Henry Stimson on the day after France's surrender, "remained between the Nazis and the Western Hemisphere -- the British Fleet." Faced with this "appalling prospect," the United States would stand alone if that fleet were lost."20

Reassurances from the British that they had no intention of giving up the fight were gratifying to a President so closely committed to British support, but a more objective estimate of Great Britain's ability to resist invasion and detailed information on which to base plans were needed. To fill this need as well as to see for themselves how the British were fighting and what they needed most, the Army and Navy sent special observers to London in the summer of 1940 at Mr. Churchill's invitation. The Army observers were General Strong, Chief of the War Plans Division, and Maj. Gen. Delos C. Emmons of the Air Corps. Both would remain for only a few weeks, but the Navy observer, Rear Adm. Robert L. Ghormley, was to remain in London on extended duty. Already, the British had appointed their own Admiralty Committee to consider "naval cooperation with the United States Navy" in the event of American entry into the war, and had made clear to the Americans in a general way how they intended to fight the war.21

With the arrival of the special observers in London in August 1940, the conversations which had been carried on informally by the Navy since December 1937 were broadened to include Army representatives and enlarged in scope to include basic questions of strategy, command arrangements, and materiel requirements. None of the observers doubted the determination of the British people to continue their resistance. In their month in England, Generals Emmons and Strong were greatly impressed by the coolness and confidence of the British under attack, and by the organization, training, and techniques for defense against air attack.22 British faith in the efficacy of air bombardment, and the independent position of the Royal Air Force had an effect also on the two Army observers. Implicit in their report was a reflection of the British belief that Germany could be so weakened ultimately by air bombardment as to make ground operations on the Continent feasible.

The American observers also learned much about British strategy for the conduct of the war. In broad terms, the British Chiefs outlined for the Americans their policy for the conduct of the war.

  1. The security of the United Kingdom


    and Imperial possessions and interests.

  1. Command of the home waters and the eastern Mediterranean, combined with an attempt to regain command of the entire Mediterranean.

  2. An intensified air offensive and economic pressures against both Germany and Italy.

  3. Development of resources for major offensive ground operations when opportunity offered.23

In the Far East, the British admitted frankly, their interests would be best served if the U.S. Fleet remained in the Pacific. Their original plan had been to send a naval force to the Far East in the event of a Japanese attack, but that was no longer possible. On the other hand, if Japan came into the war and if the United States sent a portion of the fleet into the Atlantic, British surface vessels from the Home Fleet and the force at Gibraltar could be sent to the Far East. "The support of the American battle fleet," observed the British Chief of the Air Staff, "would obviously transform the whole strategical situation in the Far East."

On the question of American material aid, the British were equally frank. In response to a question from Admiral Ghormley as to whether the British were relying on economic support and eventual co-operation of the United States, they replied that in the plans for the future "we were certainly relying on the continued economic and industrial cooperation of the United States in ever-increasing volume." American supply, they declared, was "fundamental to our whole strategy." But on the question of the "eventual active cooperation" of the United States, the British Chiefs were somewhat evasive. "No account had been taken" of this possibility, they told the Americans, "since this was clearly a matter of high political policy."

For the British, Germany was clearly the main enemy and the "mainspring" of the Axis effort in Europe. Arguing from this basis, the British insisted that "whatever action may be necessary against any other country must, therefore, be related to our main object, which is the defeat of Germany" -- a statement that came very close to the basic strategic decision of World War II. And when Admiral Ghormley asked the British how they expected to defeat Germany and whether the final issue would be decided on land, they replied that "in the long run it was inevitable that the Army should deliver the coup de grace." But they hoped that the Army's task could be made considerably easier by "a serious weakening in the morale and fighting efficiency of the German machine, if not a complete breakdown." How this would be accomplished, the British did not specify, but their emphasis on bombardment indicated that air power would certainly play a leading role in the defeat of Germany.

Shift to the Atlantic, September 1940-January 1941

Events in Europe after June 1940 gave hope for a brighter future than had seemed possible after the German offensive in April and May. The success of the British in beating off the attacks of the Luftwaffe and the reports of the special observers led to a more favorable program of support for the British war


effort and to other measures such as the transfer of fifty old destroyers in return for a lease on British air and naval base sites in British possessions in the western Atlantic. For the moment, the Axis threat in Europe seemed to be blunted.

Meanwhile, the situation in the Far East had taken a turn for the worse. On 22 September, Japanese troops entered northern Indochina, and five days later the Japanese Government announced its adherence to the Rome-Berlin Axis. Just two days before the signing of the Tripartite Pact, the Army planners had completed a report on the ability of the United States to cope with the problems presented by the Axis threat. After reviewing the possibilities in Europe, the planners pointed out that the United States might soon face renewed advances in the Far East, possibly against the Netherlands Indies or the Philippines, but that it would not be possible to oppose such moves by a major effort in the Pacific in view of the greater danger in the Atlantic. Operations in the Pacific, they maintained, should be held to the minimum.24

There was general agreement in Washington with this view. The main problem was how to avoid a conflict with Japan and at the same time maintain American interests and defend American possessions in the Far East. The answer perhaps lay in Europe, for there was strong reason to believe that Japan would take no overt military action against the United States or Great Britain until German victory seemed assured. This line of reasoning served to strengthen the view that as long as Great Britain was in danger, the United States should remain on the defensive in the Pacific. It was also a powerful argument for continued aid to Britain, and for opposition to any move that might risk serious hostilities with the Japanese.

Early in October, the entire subject of American policy toward Japan was reviewed on the highest level in Washington. Inevitably the question of British co-operation arose. The military chiefs opposed strong action on the ground that the British would be unable to send any forces into the area and that the United States could not undertake to assume Allied obligations in the Far East. Despite the well-known views of the American staff, the British continued their efforts to persuade the Americans to join the defense of their Far Eastern possessions by sending naval units to Singapore. In May 1940, Churchill had offered to let the Americans use Singapore "in any way convenient" in order, as he put it, to "keep the Japanese quiet in the Pacific." On 4 October he tried again. In a strong personal message to President Roosevelt discussing the Far Eastern situation, he asked, "Would it not be possible for you to send an American Squadron, the bigger the better, to pay a friendly visit to Singapore? There they would be welcomed in a perfectly normal and rightful way."25

Both Admiral Stark and General Marshall were opposed to the dispatch of an American naval force to Singapore and agreed that the greater danger was in the eastern Atlantic. Secretary Hull also opposed the move. As he told the British Ambassador, "It will not be wise,


even from the British standpoint, for two wars to be raging at the same time, one in the East and the other in the West. If this country should enter any war, this would immediately result in greatly cutting off military supplies to Great Britain."26 The move would be politically inexpedient also, for this was an election year and Roosevelt was already in the midst of a campaign for election to a third term. A military gesture such as Churchill had proposed was likely to lose more votes than it would gain. Thus, on grounds of political expediency as well as strategy, the President turned down Mr. Churchill's invitation.

Yet developments since the summer of 1940 had made the need for a closer co-ordination of British and American plans increasingly evident. Almost every important problem faced by the military planners raised questions that could not be settled without an intimate knowledge of British capabilities and plans. But the hectic months of a Presidential campaign and the uncertainty of the outcome discouraged any serious effort to lay the basis for such co-ordination. By early November, President Roosevelt's re-election seemed certain and on the eve of the election Admiral Stark made the first bid for a firm and clear statement of American policy that would provide the basis for co-ordinated U.S.-British plans.27 It was the strongest and most comprehensive analysis thus far of the various courses of action open to the United States, the military effect of developments in Europe and Asia, and the close relationship between British fortunes and American policy. Known as the "Plan Dog" memorandum because the recommended course of action if the United States became a belligerent was contained in paragraph D ("Dog" in military parlance), Admiral Stark's study constitutes perhaps the most important single document in the development of World War II strategy.

The central point of Admiral Stark's analysis was the recognition that American security depended to a very large extent on the fate of Great Britain. This note he sounded at the very outset with the assertion that "if Britain wins decisively against Germany we could win everywhere; but that if she loses the problems confronting us would be very great; and while we might not lose everywhere, we might, possibly, not win anywhere." Should the British Empire collapse, it seemed probable to Stark that the victorious Axis powers would seek to expand their control, economically at first and then politically and militarily, into the Western Hemisphere. The military consequences of a British defeat were so serious for the United States, Stark declared, that the British ought to be assisted in every way possible. He did not believe, either, that Britain had the manpower or material resources to conquer Germany alone. Assistance by powerful allies would be necessary ultimately, and to be ready for this eventuality Britain "must not only continue to maintain the blockade, but she must also retain intact geographical positions from which successful land actions can later be launched."


In facing the consequences of close co-operation with the British, Admiral Stark boldly raised the possibility -- thus far avoided -- of active American participation in the war. Since Britain could not herself defeat Germany, the question was how American resources in men and supplies could be employed in combination with the British to achieve this end. Admiral Ghormley, it will be recalled, had raised this question with the British in London in August, asking whether large-scale ground operations would be necessary. He had received an affirmative reply from the British then, and Stark now returned to this point. Blockade and bombardment, the means favored by the British, he did not think would do the job. The only certain way of defeating Germany was "by military success on shore," and for that, bases close to the European continent would be required. "I believe," Stark declared, "that the United States, in addition to sending naval assistance, would also need to send large air and land forces to Europe or Africa, or both, and to participate strongly in this land offensive."

Considering the importance of the Atlantic to American security, Stark argued strongly against major commitments in the far Pacific that would involve the United States in an all-out effort against Japan, as envisaged in Orange. Such a course would have the effect of drawing resources away from the Atlantic and cutting down aid to Britain. Even a limited war against Japan would require strong reinforcements in the Southwest Pacific and Southeast Asia to defend British and Dutch possessions. Also, it might prove very difficult indeed to prevent a limited war from becoming unlimited, as the Japanese later found out. Nor did Stark see how the defeat of Japan, even if this could be accomplished, would contribute materially to the more important objectives of the defense of the Western Hemisphere and the continued existence of the British Empire. To perform all the tasks required to achieve these objectives, the United States could "do little more in the Pacific than remain on a strict defensive."

The major alternative courses of action open to the United States, as Stark viewed the possibilities, were four, and he stated them as questions:

  1. Shall our principal military effort be directed toward hemisphere defense and security in both oceans? (Similar to RAINBOW's 1 and 4.)

  2. Shall we prepare for a full offensive against Japan, premised on assistance from the British and Dutch forces in the Far East and remain on the strict defensive in the Atlantic? (Similar to RAINBOW 2, or RAINBOW 3 and Orange with allies.)

  3. Shall we plan for sending the strongest possible military assistance both to the British in Europe and to the British, Dutch and Chinese in the Far East? (In effect, this would call for an equal effort on two fronts while defending the Western Hemisphere.)

  4. Shall we direct our efforts toward an eventual strong offensive in the Atlantic as an ally of the British, and a defensive in the Pacific? (Similar to RAINBOW 5.)

There was no doubt in Admiral Stark's mind that the alternative outlined in paragraph "Dog" would best serve the national interests. It would enable the United States to exert all its effort in a single direction, make possible the greatest assistance to Britain, and provide the strongest defense of the Western Hemisphere. The one great disadvantage of the Plan Dog, of course,


was that it would leave Japan free to pursue her program of expansion in Asia and the Southwest Pacific. Therefore the United States, while making every effort to avoid war with Japan, should seek to keep that nation from occupying British and Dutch possessions in the Far East.

Plan Dog was the course to be followed in the event of war -- and Stark seemed to have little doubt that the United States would soon be involved in the European conflict. But if war did not come, or, as he put it "until such time as the United States should decide to engage its full forces in war," the best course to follow would be that outlined in paragraph A, that is, to build up the defenses of the Western Hemisphere and stand ready to fight off a threat in either ocean.

Admiral Stark also had a program for carrying out the policy he proposed. The first step would be to prepare a joint plan as a guide for Army and Navy planning, and at least the "skeleton" of alternative plans for other situations that might develop. Such plans, however, would be of limited value, he pointed out, if there was not a "clear understanding between the nations involved as to the strength and extent of the participation which may be expected in any particular theater. . . ." For this reason, therefore, Stark recommended that secret staff talks be initiated with British military and naval authorities "to reach agreements and lay down plans for promoting unity of allied effort should the United States find it necessary to enter the war."28

The reaction of General Marshall and the Army planners to Plan Dog was entirely favorable. As a matter of fact, the Army had argued substantially along these lines in June 1940, when the prospect of an Axis victory in Europe had seemed so great, and General Marshall had then asked whether it would not be advisable to reframe U.S. naval policy so as to place the main effort in the Atlantic with "purely defensive action in the Pacific."29 Thus, except for minor comments, the Army planners endorsed the Stark proposals, which went forward to the President on 13 November. On the 18th, the Joint Board instructed its planning committee to study the questions raised by Admiral Stark and prepare recommendations for submission to the President and the two service Secretaries."30

The British, who presumably learned of Plan Dog from Admiral Ghormley, also agreed with Admiral Stark. Since the plan was based so largely on the need to maintain the British Empire, this is not surprising. Churchill thought the plan "strategically sound" and "highly adapted to our interests," as indeed it was, but only because of the identity of British and American interests. He was "much encouraged by the American naval view," and cautioned his staff "to strengthen the policy of Admiral Stark"


and "not use arguments inconsistent with it."31 Apparently the British Chiefs took this advice seriously for on 23 November Admiral Ghormley reported to Stark that in the view of the Admiralty, which he believed to be the view of the British Government, "the primary objective of the war is the defeat of Germany and Italy," and that in case Japan and the United States should enter the war, U.S.-British strategy in the Pacific should be to contain the Japanese and prevent extension of the operations to the south and to the Indian Ocean.32 But the British clung to their faith in Singapore, and still hoped the United States would send a naval force there to hold it against the Japanese.

While arrangements went forward for conversations with the British, the joint planners continued their efforts to produce a statement of national defense policy based on Admiral Stark's recommendation. If acceptable, this document was to be submitted for approval to the President by the Secretaries of State, War, and Navy, and serve as the basis for instructions to the American representatives in the forthcoming staff conversations. On 21 December 1940, the joint planners completed their work. In all essential respects, their recommendations were similar to those of Admiral Stark. The major objective of U.S. defense policy, they said, was the security of the Western Hemisphere, and this was to be secured by full cooperation with the British Commonwealth. Until forced to enter the war, the United States should follow the course advocated in paragraph A of Stark's memorandum; if forced into war with Japan, the United States should at the same time enter the war in the Atlantic and limit operations in the mid-Pacific and Far East so as "to permit prompt movement to the Atlantic of forces fully adequate to conduct a major offensive in that ocean."33 American policy and strategy, therefore, would be designed to defeat Germany and her allies in order to prevent the extension of Axis influence into the Western Hemisphere, while seeking to keep the Japanese from entering the war or from attacking British and Dutch territory in the Far East.

The Joint Board approved the work of its planners on 21 December, and the Secretaries of War and Navy gave their approval soon after. The original intention was to have the Secretary of State join the two service Secretaries in submitting these recommendations to the President for his approval as the basis for future action by all agencies of the government. But Mr. Hull refused. He was in general agreement with these policies, he declared, but was doubtful of the propriety of "joining in the submission to the President of a technical military statement of the present situation."34

Arrangements for staff conferences with the British were completed early in January 1941, and on the 15th of the month the British delegation left for the


United States. There had been preliminary exchanges of view by cable and a proposed set of instructions had been prepared for the American representatives. But the military authorities still did not have President Roosevelt's approval of the recommended national defense policy, which was to constitute the guide lines for the American delegates. Finally, on 16 January, the President met with his military advisers, the two Secretaries and the service Chiefs. Present at the meeting also was the Secretary of State, who, with the others constituted a group known informally as the "War Council."

The meeting opened with a consideration of the problems raised by the possibility of simultaneous action by Germany and Japan against the United States. The President thought there was only "one chance in five" of such an attack but he avoided any commitment on the basic question of whether to plan for a major effort in the Atlantic or Pacific. On one point, though, he left no doubt. There was to be no curtailment of aid to Britain, even in the event of a concerted attack in the Atlantic and Pacific. Clearly, the President's major concern was with Great Britain. In that sense, he was of the same mind as his chief military and civilian advisers. He thought the Navy should be prepared to convoy shipping in the Atlantic and continue to patrol the coast. But he was equally anxious that the Army should not be committed to any operations until it was fully prepared, and that American military policy should be "very conservative" until its strength had been greatly increased. In Latin America, the United States would have to be prepared, the President declared, to provide forces, properly trained, to assist the governments in their resistance to subversive Axis activity.

The President's view of American policy in the Pacific coincided closely with that of the military authorities. There the United States would stand on the defensive with the fleet based on Hawaii. There was to be no naval reinforcement of the Philippines, and the Commander of the Asiatic Fleet, based in the Philippines, was to have discretionary authority in the event of attack to withdraw when he thought it necessary. The choice was his and it would be up to him to decide whether to sail east toward Pearl Harbor or south to Singapore, as the British wished.35

By the middle of January 1941, the major lines of American strategy in World War II had emerged and the reelection of President Roosevelt assured a continuation of the policy established during the critical summer months of 1940. While hoping to achieve his aims by measures short of war, the President had publicly stressed during the preceding months America's unreadiness for war and the danger from Europe and the Far East. Army and Navy planners had defined the problem facing the United States in a series of studies, and had made plans to meet various situations which might arise. The most likely contingency in early 1941 was that the United States, allied with Great Britain, might be involved in a two-ocean war against a combination of Germany, Italy, and Japan. In such a contingency, it was generally agreed, the United States would adopt a defensive role in the Pacific and make its main effort against


the most powerful and dangerous enemy, Germany. But before firm plans could be made, it was first necessary to reach agreement with Great Britain on the broad aims of the war and the major outlines of strategy.


During the first three weeks of January 1941 the planners of the Joint Board completed their arrangements for the American-British staff conference. On 21 January, they submitted to the board a proposed agenda for the meetings and a statement of the American position. The meetings were to be nonpolitical; no specific commitments were to be made "except as to technical method of cooperation," and agreements reached would be subject to approval by the two governments. Within this framework, the delegates were to determine the best methods by which the forces of both nations could defeat Germany and its allies should the United States be "compelled to resort to war" -- a phrase introduced by the President; reach agreement on the methods and nature of military co-operation; and co-ordinate plans for the use of their forces.

As a guide for the delegates, American national objectives were defined in virtually the same terms used by Admiral Stark: (1) protection of the Western Hemisphere against military or political encroachment by any other power; (2) aid to the British Commonwealth; (3) opposition by diplomatic means to Japanese expansion. In the event of war, the "broad military objective" of the United States and Britain would be the defeat of Germany, which would be "most effectively attained" by placing the principal military effort in the Atlantic, or "navally in the Mediterranean" -- another Presidential phrase. In the way of practical advice in negotiating with the British, the delegates were to keep the following in mind:

It is believed that we cannot afford, nor do we need, to entrust our national future to British direction. . . .

United States Army and Navy officials are in rather general agreement that Great Britain cannot encompass the defeat of Germany unless the United States provides that nation with direct military assistance. . . .

It is to be expected, that proposals of the British representatives will have been drawn up with chief regard for the support of the British Commonwealth. Never absent from British minds are their postwar interests, commercial and military. We should likewise safeguard our own eventual interests.36

The Joint Board gave its approval to these instructions and procedures on 22 January, submitting them in turn to the Secretaries of War and the Navy with the suggestion that the statement defining the military position and strategy governing the action of U.S. forces be approved by the President. As a result Secretary of the Navy Frank Knox personally submitted the report to the President on the 23d and three days later Roosevelt approved it with minor changes in wording.37

The American-British staff conversations opened in Washington on 29 January 1941 and continued through fourteen sessions to 29 March, when the delegates


submitted a final report, commonly known as ABC-1.38

At the outset, the British stated their position clearly and fully:

  1. The European Theater is the vital theater where a decision must first be sought.

  2. The general policy should therefore be to defeat Germany and Italy first, and then deal with Japan.

  3. The security of the Far Eastern position, including Australia and New Zealand, is essential to the cohesion of the British Commonwealth and to the maintenance of its war effort. Singapore is the key to the defense of these interests and its retention must be assured.

In line with this strategy, U.S. naval forces, after appropriate dispositions for defense of the Western Hemisphere, should be employed mainly in the Atlantic and Mediterranean, the British stated. But they also declared that the United States should maintain in the Pacific a fleet large enough to prevent the Japanese from prejudicing the main effort in the Atlantic.

There was no disagreement between the Americans and the British on the first two points. Both sides were agreed that Germany was the main enemy and the first objective of the allies. They agreed further that the Atlantic would be the decisive theater of the war and the principal effort of the two nations would be made there. The delegates also recognized the legitimate interests of each side, an indispensable basis for co-operation. On the American side, the security of the United States and the defense of the Western Hemisphere were considered of paramount interest, with first call on American forces. British interests were broader, encompassing the security of the British Commonwealth of Nations. "A cardinal feature of British strategic policy," the delegates agreed, "is the retention of a position in the Far East such as will insure cohesion and security of the British Commonwealth and the maintenance of its war effort."

The third point of British strategy, the importance of Singapore, involved the whole question of Far Eastern strategy. On this, there was a fundamental disagreement between the British and American delegates. This disagreement stemmed partly from different national interests. The British had to deal with problems of imperial security, and in their view Singapore was essential to the defense of India, Australia, and New Zealand. American interests in the Far East, though substantial, were not as vital. The only American possession of importance in the area, the Philippines, had virtually been written off as indefensible in a war with Japan.

There was a basic difference in outlook also between the British and Americans. Reflecting their insular position and long tradition in wars against Continental powers, the British placed their main emphasis on sea and air power rather than large-scale ground forces. The reduction of Germany by these means would be a slow process, but the British were accustomed to long wars and had no doubt of ultimate victory. The final blow, they expected, would be delivered by ground armies, but to prepare for that eventuality they would first secure or regain the strategic positions required for the offensive -- Singapore, the Mediterranean -- and then concentrate


on weakening the enemy's war machine. Victory with minimum losses and minimum risks, exploitation of superior naval power, and avoidance of large-scale continental operations -- that was the classic British strategy.

The Americans, conscious of their overwhelming material resources and unwilling to face the prospects of a long war, wished to concentrate all their power at the earliest possible moment against the main enemy. To achieve this aim and end the war quickly with fewer casualties in the long run, they were willing to face the temporary loss of strategic positions like the Philippines and to risk substantial casualties initially rather than disperse their forces or adopt a purely defensive or delaying strategy.

These differences emerged sharply in the discussions over Singapore. What the British were asking the Americans to do was to underwrite the defense of the Empire and incorporate, as a central feature of Allied strategy, the British concept of the importance of Singapore as the key to defense of the Far East, even at the expense of concentrating for a decisive blow against Germany at the earliest possible date. Though the Americans appreciated the political, economic, and symbolic significance of Singapore for the British Empire, they doubted its strategic value and the wisdom of underwriting its defense. To accept the British proposal would not only have been contrary to their instructions but would constitute, the American delegates believed, "a strategic error of incalculable magnitude."39 They therefore refused to budge from the position that the British must look after their own special interests, as the United States would look after its own in the Philippines, and that the two nations should act together where their interests coincided -- in the North Atlantic and the British Isles.

The report submitted by the American and British delegates laid down the basic guide lines of Allied co-operation in World War II. It defined clearly the policies, the "paramount interests" of both countries, and the general strategic concepts designed to support these policies. Among the major strategic objectives accepted by both sides were the following:

  1. The early defeat of Germany as the predominant member of the Axis, with the principal military effort of the United States being exerted in the Atlantic and European area, the decisive theater. Operations in other theaters to be conducted in such a manner as to facilitate the main effort.

  2. The maintenance of British and Allied positions in the Mediterranean area.

  3. A strategic defensive in the Far East, with the U.S. Fleet employed offensively "in the manner best calculated to weaken Japanese economic power, and to support the defense of the Malay Barrier by directing Japanese strength away from Malaysia."

To secure these objectives, the delegates agreed on a number of specific measures, including economic pressure, a sustained air offensive against German military power, the early elimination of Italy from the war, raids and minor offensives at every opportunity, and the support of resistance movements in Axis-dominated countries. All these would be preparatory to the final offensive


against Germany. For that it would be necessary to secure bases in the Mediterranean and on the west and northwest shores of Europe, and to gather "maximum land forces, composed largely of mobile armored divisions" to defeat and destroy the German Army.

The agreements reached between the American and British staffs and embodied in ABC-1 were not intended to be binding on the two nations or to have any political or official character, but only to determine the way in which the United States and the British Commonwealth could defeat Germany "should the United States be compelled to resort to war." From the start it was understood that conclusions reached by the conferees would have to be confirmed by the Chiefs of Staff of both nations and were contingent upon political agreements by the two governments. In line with this understanding, General Marshall and Admiral Stark gave their tentative approval to the report and advised the British Chiefs that they would present it to the President for approval at an appropriate time.40 At the same time, the Joint Board issued a new directive for the preparation of RAINBOW5, the situation most closely meeting the requirements laid down in ABC-1.

Work on RAINBOW 5 had been initiated originally in May 1940, after the German offensive in the west but before the fall of France. The situation envisaged then in RAINBOW 5 was a war in which the United States, allied with Great Britain and France, would project its armed forces "to either or both of the African and European continents as rapidly as possible" to accomplish the decisive defeat of Germany. The planning done in May on this basis was rendered obsolete within a month by the fall of France. Moreover, it seemed doubtful at the time that Great Britain would survive, and the planners turned their efforts to other RAINBOW situations -- first RAINBOW 4 (hemisphere defense), and then RAINBOW 3 (United States alone in a major effort against Japan) . By the end of 1940, when it appeared that Britain would survive and a revised RAINBOW 5 situation was the most likely contingency for which to plan, arrangements were already under way for the American-British staff conversations.

Once the Chief of Staff and Chief of Naval Operations had given their approval to ABC-1, work on RAINBOW 5 progressed rapidly. By 30 April, the Army and Navy had agreed on a joint plan and on that date submitted their work to the Joint Board. For the purposes of this plan, the Allies-Associated Powers, they were called -- were assumed to be the United States, the British Commonwealth (less Eire), the Netherlands Indies, Greece, Yugoslavia, China, the Governments-in-Exile, and the Free French; the Axis nations, Germany, Italy, Rumania, Hungary, Bulgaria, and possibly Japan and Thailand. These last two, even if they were not in the war initially, were potential enemies and the possibility of their intervention was therefore taken into account in the plan.41

RAINBOW 5 was virtually identical with ABC-1. As a matter of fact, one of the first assumptions of the plan was


that the Allies would conduct the war "in accord with ABC-1." Thus, the strategic concepts, supporting measures, and missions enumerated in ABC-1 were repeated almost verbatim in RAINBOW 5. For the U.S. Army, "the primary immediate effort" would be to build up large land and air forces "for major offensive operations against the Axis powers" and other operations were to be restricted to those that would "not materially delay this effort." Just what these operations would consist of was not specified, although reference was made, as in ABC-1, to a large-scale attack by ground forces against Germany and to the capture of bases from which to launch such an offensive. As one of the Army planners explained at the time, " a plan must be formulated upon a situation and no prediction of the situation which will exist when such a plan can be implemented should be made."42

RAINBOW 5 was neither a blueprint for victory nor a plan of operations. It merely outlined the objectives and missions of American forces in case of war on the basis of assumptions that seemed sound at the time. Specific plans to achieve these objectives were still to be made. The first step was to secure authority to proceed.

Joint Board authority came on 14 May when the board formally approved both RAINBOW 5 and ABC-1, which it had tentatively approved early in April. Approval by the Secretaries came on 28 May (Navy) and a June (Army), at which time both plans went to the President, with the explanation that the British Chiefs of Staff had approved ABC-1 provisionally and submitted it to their government for approval. The President apparently read the two documents carefully but withheld approval of ABC-1 on the ground that the British had not yet approved it. Nor would he approve RAINBOW 5, presumably because it was based on ABC-1, that is, on arrangements with the British which had not yet been accepted by that government. He did request, however, that "in case of war" the two plans be returned to him for his approval.43

The President's ambiguous response to the carefully worked out arrangements with the British, and to the American plans based on these arrangements, raised the question of whether the Army and Navy were authorized to proceed with their own planning for war on a RAINBOW 5 contingency. This question was resolved on 10 June at a meeting in Mr. Stimson's office. General Marshall's view was that since the President had not disapproved the plan, the Army could proceed with its own arrangements. This seemed reasonable, and it was on that basis that the services proceeded to make detailed plans for the employment of their forces.44

By the middle of 1941 American policy and military strategy had subordinated the Pacific to a secondary position, while maintaining that the United States would defend its overseas possessions and its interests in the Far East. The danger of war with Japan was a real one, but


in the face of the greater threat from Germany it had been decided to place the main effort in the Atlantic and to restrain Japan by political and economic means. If Japan did attack, the United States would have to limit itself to the defense of that area in the Pacific vital to its security, Alaska-Hawaii-Panama, and accept the loss of the Philippines, Wake, and Guam. But there were some who still believed that the Philippines could and should be reinforced and that the obligation of the United States to the Filipinos and its position in the Far East transcended the logic of the military strategists.

The circumstances under which a war with Japan would begin were not yet known and, except for local defense plans, there was no settled solution on a plan to defeat Japan. The general pattern of the war and the courses of action open to American forces had been fixed over a long period of time. That the fleet would advance step by step across the Pacific through the Mandated Islands, specifically the Marshalls and the Carolines, to the Philippines, and that it would then seek to establish supremacy in the western Pacific was well understood and accepted. But beyond the general statement that Japan would be brought to her knees by economic pressure, blockade, and air bombardment, there was no specific plan for operations to defeat the enemy. Moreover, though it was assumed that British, Dutch, and Chinese forces would fight the common enemy, there were no plans for concerted action and there was still disagreement between the American and British planners over the role of Singapore. There was much still to be done -- forces to be raised, weapons produced, and plans written. Until then, the United States would have to restrain an increasingly aggressive Japan by all means short of war.


Table of Contents ** Previous Chapter [2] ** Next Chapter [4]


1. The material covered in this chapter has been treated more fully from different points of view and with different emphases in a number of works in the series UNITED STATES ARMY IN WORLD WAR II: Maurice Matloff and Edwin M. Snell, Strategic Planning for Coalition Warfare, 1941-1942 (Washington, 1953), chs. I-III; Watson, Chief of Staff: Prewar Plans and Preparations, chs. IV, X, and XII; Richard M. Leighton and Robert W. Coakley, Global Logistics and Strategy, 1940-1943 (Washington, 1953), pt. one; Stetson Conn and Byron Fairchild, The Framework of Hemisphere Defense (Washington, 1960), chs. I-V; and also in William L. Langer and S. Everett Gleason, The Undeclared War, 1940-1941 (New York: Harper & Brothers, 1953). The present account is based on the original sources, except where otherwise indicated, and has appeared in slightly different form in Kent R. Greenfield, gen. ed., Command Decisions (New York: Harcourt, Brace and Company, 1959).

2. For an account of the staff conversations in London early in 1938, see Pearl Harbor Attack Hearings, pt. 9, pp. 4272-78 and Capt. Tracy B. Kittredge, U.S.-British Naval Cooperation, 1939-1945, sec. I, pt. C, pp. 37-38, MS in OCMH.

3. Mins, JB Mtg, 9 Nov 1938.

4. Mins, JB Mtg, 6 May 1939; Ltr, JPC Rpt. Exploratory Studies, 21 April 1939, JB 325, ser. 634. The discussion of the report is based on the Exploratory Studies and related papers in the same file.

5. The first directive of the Joint Board was dated 11 May 1939, but on further study was revised and amended instructions issued on 30 June. Mins, JB Mtg, 6 May 39, and 30 June, JB 325, ser. 634; Ltrs, JB to JPC, 11 May 39, sub: Joint Army and Navy Basic War Plans,, RAINBOW's 1, 2, 3 and 4; JPB to JB, 23 Jun 39, same sub; JB to JPC, 30 Jun 39, same sub. All in JB 325, ser. 642 and 642-1.

6. Kittredge, U.S.-British Naval Cooperation, sec. I, Part D, Notes pp. 42-46; Memo, JPC to JB, 23 Jun 39; Mins, JB Mtg, 30 Jun 39, JB 325, ser. 642.

7. Joint War Plan RAINBOW 1, JB 325, ser. 642-1. Approved by the Joint Board on 9 August, by the Secretary of War and Secretary of Navy on 14 August 1939, and by the President orally two months later.

8. Mil Order, 5 Jul 39; Memo of Secy JB, 20 Jul 39, JB 346, ser. 646.

9. The various drafts of RAINBOW 2 can be found in the Army files of the JPC, JB 325, ser. 642-2.

10. Mins, JB Mtgs, 22 Feb and 10 Apr 1940; JPC to JB, 9 Apr 40, sub: Joint War Plans RAINBOW, approved 10 April, JB 325, Ser. 642-1. The priorities established for RAINBOW planning at this time were

  1. Complete RAINBOW 2.
  2. Develop RAINBOW 3 as far as the main courses of action.
  3. Develop RAINBOW 5 as far as the main courses of action.
  4. Complete RAINBOW 3. AINBOW 5.
RAINBOW 4 was assigned the lowest priority and no planning for it was scheduled.

11. The alert message is reproduced in Pearl Harbor Attack Hearings, pt. 15, p. 1594.

12. Memos, WPD for CofS, 22 May 40, sub: National Strategic Decisions; CofS for WPD, 23 May 40, so sub; Aide Mèmoire, Maj Matthew B. Ridgway, 23 May 40. All in WPD 4175-10.

13. Ltr, JPC to JB, 31 May 40, sub: Joint Army and Navy Basic War Plan RAINBOW 4. The Joint Board approved the plan early in June and the Secretaries soon after. it was not approved by the President until 14 August. Relevant papers are in JB 325, ser. 624-4.

14. Joint War Plan RAINBOW 4, JB 325, ser. 624-4.

15. Memo, Sr Army and Navy members JPC to Dirs WPD, 16 Jun 40, WPD 4250-3.

16. Notes on Conf in OCofS, 17 Jun 40, Misc Confs, binder 3.

17. Memo, WPD for CofS, 17 Jun 40, sub: National Defense Policy, WPD 4250-3.

18. The relevant papers are filed in WPD 4250-3.

19. Memo, CofS and CNO for President, 27 Jun 40, sub: Basis for Immediate Decisions. . .. ; see also preliminary studies by the planners with the President's comments, in WPD 4250-3.

20. Henry L. Stimson and McGeorge Bundy, On Active Service in Peace and War (New York: Harper & Brothers, 1948), pp. 318-19.

21. For a complete account of these developments and naval conversations, see Kittredge, U.S.-British Naval Cooperation, sec. III, pt. A and B.

22. Memo, Emmons and Strong for CofS, 22 Sep 40, sub: Observations in England, WPD 4368.

23. Minutes of the meetings with the British are in WPD 4402-1.

24. Memo, WPD for CofS, 25 Sep 40, sub: Problem of Production. . . , WPD 4321-9.

25. The message is quoted in Winston S. Churchill, Their Finest Hour (Boston: Houghton Mifflin Company, 1949), pp. 497-98

26. Memoirs of Cordell Hull, I, 906.

27. Memo, Stark for Secy Navy, 12 Nov 40, no sub. This is a revision of the original 4 November memorandum, no copies of which are in the Army file, revised to include the Army WPD comments and sent to the President. All papers relevant to this memo are filed in WPD 4175-15.

28. The British had already suggested such conversations on various occasions. The most recent suggestions were made in October by the British Ambassador to Secretary Hull in Washington, and by Admiral Sir Dudley Pound to Ghormley in London.

29. Notes of Conf in OCS, 17 Jun 40, sub: Defense Problems, OCS Misc Confs.

30. Ltr, CofS to JB, 18 Nov, sub: National Defense Policy for the United States, JB 325, ser. 670; memos, WPD for CofS, 13 Nov 40, sub: National policy of the U.S.; Secy, Gen Staff for WPD, same date, no sub; CofS for Secy War, same date, no sub. All in WPD 4175-15.

31. Churchill, Their Finest Hour, pp. 690-91. The quotations are from his message of 22 November 1940 to the First Sea Lord.

32. Ghormley to Stark, 23 Nov 40, quoted in Kittredge, U.S.-British Naval Relations, sec.. III, pt. D, p. 313, and Notes, app. B. Records of Admiralty Meeting, 22 Nov 40.

33. Ltr, JPC to JB, 21 Dec 40, sub: National Defense Policy for the U.S., JB 325, ser. 670. Earlier drafts and directives are in the same file. See also relevant papers in WPD 4175-15 and JB 325, ser. 674.

34. Memo, Brig Gen Leonard T. Gerow for CofS, 3 Jan 41, sub: Conf with Secy State, WPD 4175-15.

35. Memo, CofS for WPD, 17 Jan 41, sub: White House Conf of 16 Jan 41, WPD 4175-18.

36. JPB to JB, 21 Jan 41, sub: Joint Instr for Army and Navy Representatives . . . , JB 325, ser. 674. The Presidential changes were made on 26 Jan; see note 37.

37. Memo, FDR for Secy Navy, 26 Jan 41, JB 325, Ser. 674; Mins, JB Mtg, 22 Jan 41.

38. Papers relating to the meeting are located in OPD Exec Files, item 11, Exec 4 and WPD 4402-1 Passim. The reports itself is found in several files, but is available in printed form in Pearl Harbor Attack Hearings, exhibit 49, pt. 15, pp. 1485-1542.

39. Memo, Army Delegates for CofS, 12 Feb 41, sub: dispatch of U.S. Forces to Singapore, WPD 4402-3.

40. Ltr, CofS and CNO to Special Army and Navy Observers in London, 4 Apr 41, sub: Tentative Approval of ABC-1, WPD 4402-18. See notation on Copy 98, Pearl Harbor Attack Hearings, pt. 15, 1485.

41. Ltr, JPC to JB, 30 Apr 41, sub: Joint Basic War Plan RAINBOW 5, incl A, JB 325, ser. 642-5.

42. Memo, WPD for CofS (May 1941), sub: Analysis of Plans for Overseas Expeditions, cited in Matloff and Snell, Strategic Planning 1941-1942, pp. 45-46.

43. Mins, JB Mtg, 14 May. The correspondence relating to the approval by the Secretaries and the statement recording the President's reaction are filed in JB 325, ser. 642-5.

44. Mins, Conf Office, Secy War, 10 Jun 41, WDCSA, Secy of War Confs, I.

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