Despite the growing tensions in Europe, it was the Japanese attack on Pearl Harbor that finally brought the United States into World War II. Ironically, Roosevelt’s efforts to help Britain fight Germany resulted in Japan’s decision to attack the United States.
America Embargoes Japan
As German submarines sank British ships in the Atlantic, the British began moving warships from Southeast Asia, leaving India and other colonial possessions vulnerable to Japanese attack. To hinder Japanese aggression, Roosevelt began applying economic pressure. Japan depended on the United States for many key materials, including scrap iron, steel, and especially oil. In July 1940, Congress gave the president the power to restrict the sale of strategic materials—items important for fighting a war. Roosevelt then blocked the sale of airplane fuel and scrap iron to Japan. Furious, the Japanese signed an alliance with Germany and Italy, becoming a member of the Axis.
In 1941 Roosevelt began sending lend-lease aid to China, hoping to enable the Chinese to tie down the Japanese and prevent them from attacking elsewhere. The strategy failed. By July 1941, Japan had sent military forces into southern Indochina, directly threatening the British Empire. In response, Roosevelt froze all Japanese assets in the United States, reduced the oil shipments to Japan, and sent General Douglas MacArthur to the Philippines to build up American defenses there.
With its war against China in jeopardy because of a lack of resources, the Japanese military planned to attack the resource-rich British and Dutch colonies in Southeast Asia. They also decided to seize the Philippines and to attack the American fleet at Pearl Harbor. Negotiations with the Americans continued, but neither side would back down. In late November 1941, six Japanese aircraft carriers, two battleships, and several other warships set out for Hawaii.
The Japanese government appeared to be continuing negotiations with the United States in good faith. American intelligence, however, had decoded Japanese messages that made it clear that Japan was preparing to go to war against the United States. On November 27, American commanders at the Pearl Harbor naval base received a war warning from Washington, D.C., but it did not mention Hawaii as a possible target. Because of its great distance from Japan, officials doubted that Japan would attack Hawaii.
The U.S. military’s inability to interpret the information that they were receiving correctly left Pearl Harbor an open target. Japan’s surprise attack on December 7, 1941, was devastating. Eight battleships, three cruisers, three destroyers, and four other vessels were sunk or damaged. The attack destroyed over 180 aircraft and killed 2,403 Americans. Another 1,178 were injured.
That night, a gray-faced Roosevelt met with his cabinet, telling them the country faced the most serious crisis since the Civil War. The next day, he asked Congress to declare war:
“As Commander in Chief of the Army and Navy I have directed that all measures be taken for our defense, that always will our whole nation remember the character of the onslaught against us. . . With confidence in our armed forces, with the unbounding determination of our people, we will gain the inevitable triumph.” ~ from his speech to Congress, December 8, 1941
The Senate voted 82 to 0 and the House 388 to 1 to declare war on Japan.
The Arizona was the US battleship that sustained the most damage and had the most casualties during the attack on Pearl Harbor.