Answer:
Declaration of state of war with Japan
Great Seal of the United States
Joint Resolution Declaring that a state of war exists between the Imperial Government of Japan and the Government and the people of the United States and making provisions to prosecute the same."
Enacted by the 77th United States Congress
Effective December 8, 1941
President Roosevelt, wearing a black armband, signs the Declaration of War on Japan on December 8, 1941
On December 8, 1941, the United States Congress declared war (Pub.L. 77–328, 55 Stat. 795) on the Empire of Japan in response to that country's surprise attack on Pearl Harbor the prior day. It was formulated an hour after the Infamy Speech of President Franklin D. Roosevelt. Japan had sent a message to their embassy in Washington, but because of problems in decoding and typing out the very long message – the high-security level assigned to the declaration meant that only personnel with very high clearances could decode it, which slowed the process – it was not delivered to the U.S. Secretary of State until after the Pearl Harbor attack. Following the U.S. declaration, Japan's allies, Germany and Italy, declared war on the United States, bringing the United States fully into World War II.
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