Final answer:
The Japanese attack on Pearl Harbor was a strategic move aimed at neutralizing the Pacific fleet and allowing Japan to carry out its expansion plans in the Pacific. The U.S.'s sanctions, including an oil and gas embargo, motivated this aggressive action. Despite some warnings, the attack was a surprise, leading the U.S. to enter World War II.
Step-by-step explanation:
The reason for the Japanese attack on Pearl Harbor, Hawaii on December 7, 1941, was tied to strategic and resource-based considerations. In August 1941, in response to Japanese aggression, the United States imposed sanctions on Japan, including an oil and gas embargo. Japan viewed the United States as an obstacle to its plan to absorb the natural resources of the South Pacific and the Philippines, a U.S. colony.
Admiral Yamamoto's strategy involved a surprise assault on Pearl Harbor, catching the U.S. forces off-guard and causing substantial damage in hopes of demoralizing the United States and weakening its Pacific fleet. This attack was engineered to give Japan a freer hand in carrying out its territorial expansions in the Pacific.
Warnings of possible war with Japan were sent to U.S. forces as U.S. intelligence services had broken various Japanese codes. Nevertheless, the Pearl Harbor attack was a devastating surprise. The day after the attack, Congress unanimously voted to declare war on Japan, signifying the U.S.'s entry into World War II.
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