Why did the japanese attack pearl harbor and how successful was the attack?

Japan moved to attack the US Navy Pacific Fleet at Pearl Harbor under the premise that war with the United States was inevitable, they wanted to strike first, to deliver a fatal blow to the American Navy that would impede the US from interfering in their conquests and military operations in Southeast Asia. A declaration of war was drafted,  but due to delays it was delivered to the US after the attack had started on December 7, 1941.  The Japanese planes inflicted terrible damage on the fleet in Hawaii, sunk several important vessels, damaged others, destroyed a hig number of aircraft and killed thousands of sailors. Nevertheless, the attack was not a full success because that day, the American carriers were not anchored at the base in Pearl Harbor, so the operation failed to achieve one of its main goals: to destroy American naval strategic capacity; the era of the aircraft carriers as the main assets of naval power had begun.

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