Japanese decision for war in 1941

While the Empire of Japan was largely committed to forcible expansion by the late 1930s, specific plans, decisions and preliminary operations (e.g. French Indochina), by the Empire of Japan, were made to begin large-scale operations of World War Two in the Pacific in December 1941, primarily in 1941 but some in 1940. These wre more detailed than broad strategic directions such as the Strike-North and Strike-South Factions, or a decision to consolidate in China and Manchuria.

Originally, the Strike-South was to have been of moderate scope, confronting only Britain. This soon expanded, though, to an inevitable confrontation with the Netherlands over Indonesia (then the Dutch East Indies). Confrontation with Australia and the United States were more complex. Japan never had serious intent to invade Australia, but recognized that Australia would be threatened by nearby activities and indeed might compete for some of the same resources. If Japan attack the Philippines, that would be a direct attack on a U.S. territory, but, even if Japan did not, there was the danger that the U.S. would support its Western allies.

The situation with France also was complex, as Japan saw Vichy as an ally. Operations in French Indochina, taken in 1940, were transitional, in that they directly bore on the Second Sino-Japanese War, but also would establish bases for Strike-South. Strike-North had largely been rejected due to the rough handling of Japanese troops, by Soviet forces, on the border, including such things as the Nomohan Incident.

1940 and Konoe

After preparatory meetings, Prince Konoe was authorized, on 17 July 1940 by Hirohito, to form a cabinet. In a meeting six days before, he had gained the support of President of the Privy Council Yoshimichi Hara, as well as four other prior prime ministers, Senjuro Hayashi, Koki Hirota, Keisuke Okada and Reijiro Watasuki. His cabinet succeeded that of Mitsumasu Yonai.

Among the key portfolios, Hideki Tojo became Army Minister and Yosuke Matsuoka and Foreign Miniser.