On October 5, 1937, Roosevelt gave a speech in Chicago, where he called for sanctions against Japan.
On July 26, 1939, the United States unilaterally denounced the trade agreement with Japan.
On July 31, 1940, under the ridiculous pretext of a shortage, the export of aviation gasoline to Japan was banned.
Roosevelt continued his unfriendly actions towards Japan, transferring $ 44 million to China in the summer of 1940, another $ 25 million in September, and already $ 50 million in November. This money was used by the Chinese government for the war with Japan.
In April 1941, he allowed American troops to be recruited into a group of "flying tigers" that had arrived in China for the war with Japan. American pilots started shooting down Japanese planes!
The Japanese government offered to hold a meeting between the Prime Minister of Japan and the President of the United States, but on August 17, 1941, Roosevelt officially refused the summit.
The last chance to resolve the problems between the countries peacefully was the arrival in the United States on November 15 of the Japanese ambassador Kurusu. He brought new Japanese proposals. In response, US Secretary of State Hull presented counter-proposals on November 26, which were essentially an ultimatum.
On December 7, 1941, Pearl Harbor was suddenly attacked by the Japanese army, which destroyed most of the US Pacific Fleet within two hours.