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Yet it was in the Pacific rather than the Atlantic that war came to the United States. When Japan joined the Axis powers of Germany and Italy, Roosevelt began to restrict exports to Japan of supplies essential to making war. Throughout 1941, Japan negotiated with the United States, seeking restoration of trade in those supplies, particularly petroleum products.
"Roosevelt, Franklin D." Encyclopaedia Britannica. 2005. Encyclopaedia Britannica Premium Service. Web. 10 Jan. 2005
According to the Encyclopaedia Britannica, President Roosevelt placed restrictions on wartime supplies to Japan following their alliance with the Axis powers ("Roosevelt, Franklin D.").