On March 22, the cabinet held a special meeting attended by prime, war, naval, financial and foreign ministers, resulting in an ambiguous plan that Japan would support Germany and Italy in principle to wage war upon the UK and the US, but not join them both currently and in the near future. Unexpectedly, disobeying the government"s wishes, Shiratori and Oshima promised in private to Germany and Italy"s foreign ministers: "Japan has the duty to go to war if Germany and Italy are attacked by any country other than the Soviet Union."
Foreign Minister Arita called in question the irresponsible promise made by the two ambassadors, but War Minister Itagaki argued that overseas ambassadors spoke on behalf of their own country, so it"s absolutely impossible to take back their statements. On April 11 Emperor Hirohito called in Itagaki, pointing out that the two ambassadors" promise without authorization offended the Emperor"s "commanding power." In August the cabinet held a second meeting attended by the five ministers, at which the navy adopted an indifferent attitude toward the tripartite alliance. Then Itagaki resorted to the army"s customary tactics -- handing in his resignation -- to bring down the cabinet. Hiranuma was forced to resign and the issue of tripartite alliance remained undecided.
Entering into fascist alliance
In July 1940 Fumimaro Konoye was authorized to form a cabinet a second time. He appointed Yosuke Matsuoka to the post of Foreign Minister, and formally put the issue of tripartite alliance on the agenda. On August 1, Matsuoka summoned German ambassador, making inquiries about Germany"s opinion on Japan-US, Japan-Soviet Union relations and putting forward a plan to establish a "Greater East Asia Co-prosperity Sphere." Afterwards, Nazi Germany sent a special envoy to Tokyo to hold talks with Matsuoka, expecting Japan to take strong and effective measures to check the US forces in the Pacific battleground.
On September 9, Konoye called a meeting attended by prime, war, naval and foreign ministers. All attendees agreed in principle to form a military alliance with Germany and Italy. On September 27, the three Axis Powers signed the treaty in Berlin to enter into military alliance, to which Shiratori made his contribution.
"Most powerful propagandist" for aggression war
After the conclusion of the Tripartite Treaty of Alliance, Shiratori was transferred to act as advisor to the Foreign Ministry. In August 1940 Konoye called to disband all political parties in the nation and set up a fascist Imperial Rule Assistance Association. On October 12 the association was established and Shiratori was chosen to be the person in charge of its general affairs.
After Japan declared unconditional surrender, Shiratori was arrested as a Class-A war criminal suspect. In November 1948 the International Military Tribunal for the Far East gave a life sentence to him for waging wars of aggression. The tribunal regarded him as the "most powerful propagandist" for Japan"s aggression war. The court decision was not based on his post, but on the fact that he overstepped his authority to serve for the militaristic, fascist regime during wartime, and entailed serious consequences, the tribunal said.
Shiratori died in prison in September 1949.