Japanese military action against the U.S. naval base at Pearl Harbor, the Hawaiian Islands, that caused America to enter the war. By early 1941, tensions between Japan and the United States had reached the breaking point. Japan's invasion of China beginning in 1937 and its occupation of French Indochina in 1940 and 1941 had led President Franklin D. Roosevelt to embargo scrap metal and oil and to freeze Japanese assets in the United States. The Japanese particularly resented the embargo on oil, characterizing it as "an unfriendly act." Japan had no oil of its own and had limited stockpiles. Without oil, the Japanese would have to withdraw from China. An army-dominated government in Tokyo now sought to take advantage of British, French, and Dutch weakness in Asia to push its own plans to secure hegemony and resources. Japan was determined to seize this opportunity, even if that meant war with the United States. The United States misread Tokyo's resolve, believing that it could force Japan to back down.
Both sides visualized the same scenario for war in the Pacific. The Japanese would seize U.S. and European possessions in the Far East, forcing the U.S. Navy to fight its way across the Pacific to relieve them. Somewhere in the Far East, a great naval battle would occur to decide Pacific hegemony. In March 1940, commander of the Combined Fleet Admiral Yamamoto Isoroku scrapped the original plan which called for using submarines and cruisers and destroyers with the Long Lance torpedo and savaging the U.S. battle fleet as it worked its way west in favor of a preemptive strike against the U.S. fleet, which Roosevelt had shifted from San Diego to Pearl Harbor on the island of Oahu. Yamamoto believed that such an attack, destroying the U.S. carriers and battleships, would buy time for Japan to build its defensive ring. Yamamoto also misread American psychology when he believed that such an attack might demoralize the American people and force Washington to negotiate a settlement that would give Japan hegemony in the western Pacific. With both sides edging toward war, U.S. Pacific Fleet commander Admiral Husband E. Kimmel and army Lieutenant General Walter C. Short made their dispositions for the defense of Oahu. Both men requested additional resources from Washington, but the United States was only then rearming, and little additional assistance was forthcoming.
The Japanese, meanwhile, trained extensively for the Pearl Harbor attack. They fitted their torpedoes with fins so that they could be dropped from aircraft in the shallow water of Pearl Harbor, and they also planned to use large armor-piercing shells to be dropped as bombs from high-flying aircraft. No deck armor would be able to withstand them.
Following the expiration of a self-imposed deadline for securing an agreement with the United States, Tokyo ordered the attack to go forward. On 16 November 1941, Japanese submarines departed for Pearl Harbor, and 10 days later the First Air Fleet, commanded by Vice Admiral Nagumo Ch?ichi, sortied. This attack force was centered on six aircraft carriers: the Akagi, Hiryu, Kaga, Shokaku, Soryu
, and Zuikaku
. They carried 423 aircraft, 360 of which were to participate in the attack. Accompanying the carriers were 2 battleships, 3 cruisers, 9 destroyers, and 2 tankers.
Surprise was essential if the attack was to be successful. The Japanese maintained radio silence, and Washington knew only that the fleet had sailed. A "war warning" had been issued to military commanders in the Pacific, but few American leaders thought the Japanese would dare attack Pearl Harbor. Nagumo planned to approach from the northwest and move in as close as possible before launching his aircraft, and then recover them farther out, forcing any U.S. air reaction force to fly two long legs.
Nagumo ordered the planes to launch beginning at 6:00 a.m. at a point about 275 miles from Pearl Harbor. Two events should have made a difference to the Americans but did not. Before the launch, American picket ships off the harbor entrance detected one Japanese midget submarine. Then they sank another. There were five Japanese midget submarines in the operation. Carried to the area by mother submarines, they were to enter the harbor and then wait for the air attack. Probably only one succeeded.
At 7:50 a.m., the first wave of Japanese aircraft began its attack on the ships at Pearl Harbor and air stations at Ewa, Ford Island, Hickam, Kaneohe, and Wheeler. Most U.S. planes were destroyed on the ground. They were easy targets as Short, to avoid sabotage by the many Japanese on the island, had ordered the planes bunched together and ammunition stored separately. The attack achieved great success. Over some 140 minutes, the Japanese sank 4 of the 8 U.S. battleships in the Pacific and badly damaged the rest. Seven smaller ships were also sunk, and 4 were badly damaged. A total of 188 U.S. aircraft were destroyed, and 63 were badly damaged. The attack also killed 2,280 people and wounded 1,109. The attack cost the Japanese only 29 aircraft and fewer than 100 aircrew dead.
The chief drawbacks in the attack from the Japanese point of view were that the U.S. carriers were away from Pearl Harbor on maneuvers and could not be struck. The Japanese failed to hit the oil tank storage areas, without which the fleet could not remain at Pearl. Nor had they targeted the dockyard repair facilities. Nagumo had won a smashing victory but was unwilling to risk his ships. The task force recovered its aircraft and departed.
Yamamoto's preemptive strike was a brilliant tactical success. The Japanese could carry out their plans in the South Pacific without fear of significant U.S. naval intervention. However, the Pearl Harbor attack also solidly united American opinion behind a war that ultimately led to Japan's defeat.
T. Jason Soderstrum and Spencer C. Tucker
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. Macon, GA: Mercer University Press, 2001.
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