November, 2, 1941.
Memorandum for the Assistant Chief of Staff, W. P. D.:
Subject: G-2 Estimate, Far Eastern Situation.
(For situation and communications maps see Tabs B, C, and D.)
In compliance with verbal request, Assistant Chief of Staff, W. P. D., this date, the following is submitted us a G-2 Estimate of the Far Eastern Situation:
1. After four years of war in China, Japan is militarily over-extended on the mainland of Asia, economically weak, and psychologically aware of the fact that her economic structure is crumbling.
2 For obvious reasons both Germany and China would like to embroil the United State in a large scale war with Japan. While Japan is reluctant to go to war with us, her political and economic situations demand action. She has the following alternatives:
a. Attack Siberia to neutralize the threat on her flank and rear.
b. Occupy Thailand as a base from which to launch an offensive against Burma or Malaya.
c. Contain or isolate the Philippine Islands and Hongkong and seize the Netherlands East Indies.
d. Launch a direct attack on Singapore.
e. Make a determined effort to bring the war in China to a close by cutting China's last supply route, the Burma Road.
f. Bide her time while disposing her forces from north to such in such a way that she will be able to seize the opportunity for successful aggression in whatever direction it presents itself.
3. A Japanese attack on Siberia is unlikely as long as Russian resistance in Europe continues, and as long as the Siberian forces are not materially reduced in strength. Action under b above might, and under c or d above would certainly bring Japan into armed conflict with ABD powers-a situation which Japan, at present, wishes to avoid.
4. A drive from Indo-China into Yunnan would probably not involve Japan with any Third Power. Although an extremely difficult operation for the Japanese, requiring elaborate preparation on their part, a successful drive into Yunnan and across the Burma Road, even if it did not cause China's early capitulation would nevertheless, be a terrific blow at her chances of holding out. It would not however, have the effect of immediately releasing any considerable Japanese force for use elsewhere, since long-drawn out mopping up operations would probably be necessary.
6. Because of the ruggedness of the terrain in southern Yunnan, and the almost complete lack of communications, the Chinese, if determined, could put up a very strong resistance even with the means now at their disposal. Such a defense would further deplete Japan's meager resources and immobilize her remaining reserves. (For a description of the terrain see Tab A.)
6. Japan's most probable line of action, therefore, will be to continue her efforts to secure a relaxation of American economic pressure while completing her plans and arranging her forces for an advance in the direction which will be most fruitful of quick results.
Brigadier General U. S. Army
Acting Assistant Chief of Staff, G-2.
(EXHIBITS OF THE JOINT COMMITTEE, PHA, PT. 14, EXHIBIT NO. 33 MILITARY INTELLIGENCE ESTIMATES PREPARED BY G-2, WAR DEPARTMENT)