<P> On December 8, 1941, the United States Congress declared war (Public Law 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 US President Franklin D. Roosevelt . Japan had sent a message for the United States to its embassy in Washington earlier, but because of problems at the embassy in decoding 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 down 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 . </P> <P> The attack on Pearl Harbor took place before a declaration of war by Japan, but that was not the intent of the Japanese leadership . It was originally stipulated that the attack should not commence until thirty minutes after Japan had informed the United States that it was withdrawing from further peace negotiations . It was the intent of the Japanese to uphold the conventions of war while still achieving surprise, but the attack began before the notice could be delivered . Tokyo transmitted the 5,000 - word notification (known as the "14 - Part Message") in two blocks to the Japanese Embassy in Washington . However, decoding and translation took too long for the ambassador to deliver it in time . Even so, the notification was worded so that it actually neither declared war nor severed diplomatic relations . </P> <P> The United Kingdom declared war on Japan nine hours before the US did, partially due to Japanese attacks on the British colonies of Malaya, Singapore, and Hong Kong; and partially due to Winston Churchill's promise to declare war "within the hour" of a Japanese attack on the United States . </P> <P> President Roosevelt formally requested the declaration in his Infamy Speech, addressed to a joint session of Congress and the nation at 12: 30 p.m. on December 8 . The declaration was quickly brought to a vote; it passed the Senate, and then passed the House at 1: 10 p.m. The vote was 82--0 in the Senate and 388--1 in the House . Jeannette Rankin, a pacifist and the first woman elected to Congress (in 1916), cast the only vote against the declaration, eliciting hisses from some of her peers . Several colleagues requested she change her vote to make the resolution unanimous--or at least to abstain--but she refused . "As a woman, I can't go to war," she said, "and I refuse to send anyone else ." Nine other women held Congressional seats at the time . After the vote, an angry mob followed her from the Capitol building, forcing her to take refuge in a telephone booth until United States Capitol Police could rescue her . Two days later a similar war declaration against Germany and Italy came to vote; Rankin abstained . Nine other women voted in favor of the declaration of war . </P>

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