Pearl Harbor Attack: Causes and Planning

• Japan's military leaders, like Hitler, aimed to build an empire, initiating expansion in 1931 with the takeover of Manchuria in northeastern China.
• By 1937, Japanese armies were further advancing into China, facing unexpected resistance that strained Japan's economy and led them to seek resources in European colonies in Southeast Asia.

Surprise Attack on Pearl Harbor

• By October 1940, the United States knew of Japan's plans for Southeast Asia due to cracked Japanese codes.
• The U.S. feared Japan's potential threat to American territories like the Philippines and Guam, should they conquer European colonies.
• To impede Japan, the U.S. bolstered Chinese resistance and, in July 1941, ceased oil shipments to Japan after they invaded French Indochina (Vietnam, Cambodia, and Laos).
• Despite the oil embargo, Japan planned simultaneous attacks on British and Dutch colonies in Southeast Asia and American outposts in the Pacific, aiming to surprise the Allied forces.
• Admiral Isoroku Yamamoto, Japan's naval strategist, advocated for an attack on the U.S. fleet in Pearl Harbor, Hawaii, deeming it a critical threat.
• On December 7, 1941, Pearl Harbor was attacked by Japan, resulting in the damage or sinking of 19 ships, including 8 battleships, and over 2,300 American deaths.
• President Roosevelt called December 7, 1941 "a date which will live in infamy," leading to Congress declaring war on Japan and its allies.
• Simultaneously with Pearl Harbor, Japan attacked Hong Kong, Guam, Wake Island, and invaded Thailand, marking the onset of their Pacific empire pursuit.

Japanese Victories

• Guam and Wake Island were quickly captured by Japanese forces, who then focused on the Philippines, entering Manila in January 1942.
• American and Filipino forces defended the Bataan Peninsula, while the Philippine government relocated to Corregidor.
• The Japanese seized Bataan in April after three months of fighting and Corregidor the following month.
• Japan also invaded Malaya via Thailand, conquering Hong Kong and reaching Singapore by February 1942, followed by the capture of the Dutch East Indies (Indonesia).
• Moving westward, Japan took Burma, planning to strike India next.
• Japan controlled over 1 million square miles of Asian land with 150 million inhabitants and initially promoted an "East Asia for the Asiatics" message but later acted as conquerors, treating new colonies cruelly.
• Allied prisoners of war faced brutal treatment, exemplified by the Bataan Death March, where approximately 70,000 prisoners were forced on a 50-mile march with only 54,000 surviving due to extreme cruelty.

The Allies Strike Back

• In April 1942, Lieutenant Colonel James H. Doolittle led 16 B-25 bombers to attack Tokyo and other Japanese cities, causing little damage but boosting American morale and exposing Japan's vulnerability.
• The Allies started to shift the war's momentum, intercepting a Japanese force headed for Port Moresby, New Guinea, in the Battle of the Coral Sea in early May 1942, halting Japan’s southward expansion.
• In the Battle of the Coral Sea ships used airplanes to attack each other
• Japan then targeted Midway Island, prompting Admiral Chester Nimitz to anticipate and counter the attack, leading to a decisive American victory that turned the tide of war in the Pacific.
• At the Battle of Midway, American pilots destroyed 332 Japanese planes, all four aircraft carriers, and one support ship.

An Allied Offensive

• General Douglas MacArthur planned to "island-hop" past Japanese strongholds, targeting less-defended islands closer to Japan.
• U.S. forces targeted Guadalcanal in the Solomon Islands, where the Japanese were constructing an air base, landing on August 7, 1942.
• The battle for Guadalcanal lasted six months, ending in February 1943 with a Japanese abandonment after losing over 24,000 soldiers, and was remembered as a horrific experience by American soldiers.