With the fighting on Eniwetok Atoll ended, U.S. forces in the Central Pacific were now free to consolidate the gains achieved by the capture of the three key positions in the Marshalls group. Three tasks remained before them. First, a host of undefended and lightly defended atolls and islands in the area had to be occupied. Secondly, air and naval bases had to be constructed to support the continued drive across the Central Pacific. Finally, the bypassed strongholds of Wotje, Mille, Jaluit, Maloelap, and Truk had to be kept under constant aerial bombardment to assure their neutralization.
Mop-up in the Marshalls
The job of occupying the various atolls and islands that the Japanese had chosen not to fortify fell largely to the 22d Marine Regimental Combat Team, with a slight assist from the 111th Infantry Regiment.1 First to be occupied were the atolls of Wotho, Ujae, and Lae, lying immediately to the westward of Kwajalein. A detachment of about 350 marines from the 1st Battalion, 22d Marines, accompanied by eight amphibian tractors, all loaded aboard an LST, landed unopposed on Wotho Atoll on 8 March and subsequently encountered twelve Japanese, the crew of a plane that had recently crash-landed on the reef. All twelve committed suicide. Two days later the same force landed without opposition on Ujae, where it discovered six enemy operators of a weather station that had previously been bombed out by American planes. Five of the Japanese committed suicide; the sixth was taken prisoner. On 13 March a landing was made on Lae Atoll. No Japanese were on the island and the natives reported that none had ever been there. The same proved to be true of Lib Island southeast of Lae.
Next to fall under American control were a number of atolls lying southeast of Kwajalein. The job of occupying these was assigned to two groups of about 325 troops each from the 3d Battalion, 22d Marines, to which were attached seven amphibian tractors, all loaded on an LST. Both groups of this force proceeded in company to Ailinglapalap Atoll for the first phase of their operation. Before any landing in force was attempted, a native was picked up who revealed that the crews of two Japanese picket boats, numbering about forty men and equipped with four machine guns and numerous rifles, were on the main island of the atoll. On the night of 20 March and the following morning, the
entire force of marines, numbering about 650, was landed without opposition. The Japanese were discovered drawn up in a prepared position, which was successfully assaulted. Thirty-seven of the enemy were killed, two taken prisoners and two or three escaped. The marines suffered three wounded. The escaped enemy were pursued around the island for a while, but the hunt was finally abandoned as futile and the marines returned to their LST to proceed to the next objective. One group went on to Namu Atoll, where it landed without opposition on 24 March. There, were found seven Japanese including one woman and four children, all of whom voluntarily surrendered. The second group proceeded to Namorik Atoll and landed on 26 March. Natives reported one unarmed Japanese on the atoll but after extensive patrolling failed to locate him, the search was finally abandoned as a waste of time.
To a detachment from the 2d Battalion, 22d Marines, fell the task of securing the group of atolls and islands lying northeast of Kwajalein. Aerial reconnaissance and the interrogation of natives indicated that Ailinginae and Rongerik Atolls were uninhabited, so the marines were ordered not to investigate them unless it should be subsequently discovered that Japanese had fled to these places after other atolls in the northern group had been captured. The first of these to be visited was Bikini, later to become famed as the site of postwar U.S. experiments with the atomic bomb. It was invaded on 28 March, and the five Japanese located on the atoll committed suicide. Three days later unopposed landings were made on Rongelap Atoll, where eleven Japanese were reported but none discovered. The same day a detachment from the 3d Battalion, 22d Marines, landed on Ailuk Atoll and discovered no enemy there. Within a few days the same force had investigated the Mejit Islands and Likiep and Utirik Atolls, netting a small bag of enemy stragglers. Finally, late in April, Company I of the 111th Infantry Regiment completed the occupation of the lesser Marshalls by capturing Ujelang Atoll, which lies about 140 nautical miles southwest of Eniwetok. The landing was made without opposition on 22 April and eighteen Japanese were flushed out and killed. Thus ended the American occupation of the Marshall Islands with the exception of Wotje, Mille, Jaluit, and Maloelap, which were left to "wither on the vine" subject to constant harassment by American planes and ships.
Building the Marshalls Bases
Immediately after Majuro Atoll was occupied, naval Seabees went ashore on Dalap Island to commence construction of an airstrip.2 When this was completed in March, it measured 4,800 by 445 feet and was thereafter constantly in use for raids against Mille, Wotje, Maloelap, and Jaluit. A naval base was established on the atoll to support two Marine dive bomber squadrons, half of a Marine patrol squadron, and temporary staging for one Army fighter group flying out of Makin against the bypassed Marshalls. In addition, Majuro provided a fleet anchorage (without shore-based facilities), medical facilities for
the fleet, and a loran transmitting station. Repair ships and submarine and destroyer tenders, together with tankers and supply ships, rode at anchor in the lagoon to supply the needs of whatever elements of the fleet passed through. Majuro, along with Eniwetok and Kwajalein, was to serve as a primary staging base for the American forces when they attacked the Marianas from June through August of 1944.
On Roi-Namur the 121st Naval Construction Battalion went ashore on 5 February, only three days after the island was declared secured. A day later it was joined by the 109th Naval Construction Battalion, and Seabees set to work immediately repairing and enlarging the Japanese airstrip on Roi. Progress was temporarily interrupted on 13 February when a flight of enemy bombers launched a heavy attack against Roi, setting fire to a bomb dump. Altogether the Seabees suffered 157 personnel casualties, and the 109th Battalion lost 75 percent of its material and 35 percent of its equipment. Nevertheless work continued, and on 15 May the field on Roi was commissioned, with a hundred planes based there. Long before the final commissioning of the field, it was in daily use as a base for strikes against Wotje, Jaluit, and Kusaie, and subsequently it became one of the primary bases for raids against Truk.
In March the 74th and 107th Naval Construction Battalions went ashore on Kwajalein Island, where they rebuilt the Japanese runway into a 6,300-foot coral-surfaced strip with two 80-foot taxiways and 102 hard stands for heavy bombers. In addition, waterfront facilities were developed to provide for minor fleet repairs, the Japanese pier reaching into the lagoon was restored, a 250-ton pontoon drydock was assembled, and a 2,000-ton floating dock was provided. On nearby Ebeye other Seabees developed a seaplane base, which was completed by April. Kwajalein Island was to become the primary base for Army bombers flying against Truk. On Eniwetok Atoll Seabees began repairs and construction work late in February. By 5 March the airstrip on Engebi was able to accommodate three Army medium bombers (B-25's), which went into action against enemy shipping at Kusaie five days later. By 20 March a 6,000-foot airstrip had been completed on Eniwetok Island as well. Parry Island was used as a small-boat repair base and a seaplane base, the ramp and facilities for servicing seaplanes being ready for use early in May.
Eniwetok Atoll thereafter served as an advanced fleet anchorage without shorebased facilities, as well as an air base capable of handling two heavy seaplane patrol squadrons, two fighter squadrons, one half of a night fighter squadron, one scout bomber squadron, two heavy bomber squadrons, and one photographic squadron. From May through October 1944, Army squadrons staging through Eniwetok and Navy and Marine squadrons based there flew continuous sorties against Truk and Ponape. In addition, Navy bombers staging through Eniwetok delivered low-level bombing and strafing attacks against Wake, and daily reconnaissance of Wake was conducted by seaplanes based on Parry.
Neutralizing the Bypassed Atolls
From February 1944 until the close of the war, that area of the middle Pacific containing the Gilberts, Marshalls, and eastern Carolines became virtually an American lake through which ships and troops passed freely with little danger of enemy interception. The reason, of course, was that the capture of key bases in the Marshalls and the establishment of airfields thereon made it possible for the superior American air arm to keep the atolls still remaining in Japanese hands under constant surveillance and bombardment.
By the time of the capture of Kwajalein, Japanese aircraft in the eastern Marshalls (Mille, Wotje, Jaluit, and Maloelap) had been either completely destroyed by Army and Navy aircraft or evacuated.3
Thereafter, the main effort of American aircraft was to prevent these bases from being reinforced and rehabilitated and to bomb out and starve out the enemy abandoned there. After mid-March, when the base at Majuro was completed, Army medium bombers flew regular flights out of Tarawa and Makin, bombed two of the bypassed islands, landed at Majuro for rearming and refueling, and then bombed the other two targets on the way home. At the same time ten fighter squadrons and
two bomber squadrons of the 4th Marine Air Base Defense Wing at Kwajalein flew a steady series of sorties against the same islands. After June 1944, Marine flyers assumed sole responsibility for these targets.4
In March two heavy bomber groups of the Seventh Army Air Force moved onto Kwajalein for the primary purpose of conducting bombing raids against Truk.5 In conjunction with planes of the Thirteenth Army Air Force based in the South Pacific, bombers of the Seventh, flying out of Kwajalein and staging through Eniwetok, kept Truk effectively neutralized from April 1944 until the end of the war.6
1. This account of the occupation of the minor atolls and islands in the Marshalls is derived from: 22d Marines Reinforced, Rpt of Operations into the Lesser Marshalls, 6 Apr 44; TU 57.10.9 Rpt, Reconnaissance of Ailinglapalap, Kili, Ebon, and Namorik Atolls, 30 Mar 44; Co 1, 111th Inf Regt, Rpt on Opns, Occupation of Ujelang, 27 Apr 44, in 111th Inf Regt Unit History, 1 Jan-31 Dec 44.
2. This account is derived from: Building the Navy's Bases in World War II, History of the Bureau of Yards and Docks and the Civil Engineer Corps, 1940-1946, Vol. II, prepared under the general supervision of the Director of Naval History, Washington, 1947, filed in Naval Records and History Division; U.S. Naval Administration in World War II, CINCPAC, Marshalls-Gilberts Area, Part IV, first draft prepared under general supervision of Director of Naval History, filed in Naval Records and History Division.
3. USSBS, The American Campaign Against Wotje, Maloelap, Mille and Jaluit, p. 35.
4. Robert Sherrod, History of Marine Corps Aviation in World War II (Washington: Combat Forces Press, 1952), Ch. VII. Mr. Sherrod has kindly allowed the authors to read this book in galley proof.
5. Craven and Cate, AAF IV, p. 672.
6. Ibid., pp. 683-86; USSBS, The Reduction of Truk.