Commentaries on War and International Relations

Pearl Harbor

Ralph Zuljan

On December 7th, 1941, at 0755 local time, a Japanese force of carrier aircraft, consisting of fighters, high-level bombers, torpedo bombers and dive bombers, began an attack on the American naval base at Pearl Harbor as well as other US military installations in Hawaii. They achieved complete surprise. Five American battleships, three cruisers and three destroyers were sunk and 188 US aircraft were destroyed (many of them on the ground). Japanese losses amounted to 29 aircraft and the five ineffectual midget submarines intended to participate in the assault. It was a brilliant tactical victory for Japan.

American attitudes contributed to the Japanese victory. US military authorities did not believe there was a serious threat of an attack on Pearl Harbor. They also believed that the harbor was immune to air launched torpedo strikes, due to its shallow waters. No American torpedo of the period could have accomplished a feat similar to that of the Japanese. New torpedoes were, in fact, developed by Japan for use in precisely these circumstances but Americans discounted what information they had about this despite the British having demonstrated that air attacks against such a harbor was conceivable, in their attack on the Italian fleet at Taranto on November 11, 1940. The implications of Taranto were studied more intensely in Japan than in the United States. Given prevailing American opinion, relatively little attention was given to the possibility of such an attack on Pearl Harbor.

American intelligence about Japanese intentions certainly showed that Japan was moving towards war with the United States and a warning that war was imminent had been issued to American forces in the Pacific at the end of November 1941 but Pearl Harbor was not ranked among the most probable targets. The lengthy Japanese note transmitted to their embassy in Washington on the day of the attack, formally breaking diplomatic relations with the US, was actually decoded by American cryptographers four hours before the attack on Pearl Harbor began (and the possibility of an attack at dawn on facilities in Hawaii was gleaned from the timing of this note) but bureaucratic inertia delayed transmission of a warning to Hawaii until after the attack had already occurred.

The local army and navy commanders (General Short, Commander, US Army, Hawaii and Admiral Kimmel, Commander-in-Chief, US Pacific Fleet) declined to take excessive precautions against an attack on their facilities because of prevailing attitudes and the lack of intelligence pointing specifically to Pearl Harbor as a target of attack. Aircraft were parked close together along the runways because greater concern was given to the risk of sabotage than to the possibility of an air attack. Torpedo nets were not deployed around the capital ships and only skeleton crews were immediately available to man the ships and antiaircraft defenses, it was a Sunday and many of the officers and sailors were onshore. Both commanders were dismissed after the attack, because of the negative impact their decisions had on American military performance during the attack.

In the final hours leading up to the attack additional warning signs were noted by local units and disregarded by command authorities. At about 0630 a US destroyer sighted what was believed to be a submarine periscope and attacked what was actually one of the midget submarines headed for Pearl Harbor. The report of this incident, however, was not taken seriously since such actions were fairly common and they were generally erroneous. One half hour later, around 0700 in the morning, operators from one of the radar stations on the island of Oahu reported detecting a number of unidentified aircraft approaching. The responsible junior officer took no action because he presumed the aircraft were American. In fact, it was the first wave of the Japanese strike force heading for Pearl Harbor.

While the litany of American errors seemed extensive, the results of the surprise attack appeared far worse at the time than could be ascribed to it later on. All three aircraft carriers serving with the Pacific Fleet were away from Pearl Harbor at the time of the attack and survived unscathed. Japanese hopes of disabling the entire US Pacific Fleet were thus dashed. Fueling and repair facilities at Pearl Harbor were also left intact. Admiral Nagumo, commanding the Japanese task force, decided against launching a third strike, targeted at the base infrastructure, because he feared that American submarines and aircraft would discover his fleet and counterattack. Nagumo reputedly commented that it would be a long war and the ships would be needed later. In his view, the attack had achieved its objective of crippling the American fleet.

Even the Commander-in-Chief of the Imperial Japanese Navy, Admiral Yamamoto, did not expect the attack to provide Japan with more than a temporary advantage. By his estimate, the best Japan could hope for by attacking first would be about six months during which it would have military superiority in the Pacific theater. By then, he believed the United States would recover and claim the initiative. The Japanese political-military leadership believed that would be enough time to gain control of the natural resources they sought and establish a firm defensive perimeter for their Pacific empire (the so-called "Greater East Asia Co-Prosperity Sphere"). They hoped that the prospect of a protracted and costly war in the Pacific, especially at a time when most of Europe was already embroiled in war, would convince Americans to accept Japanese hegemony in Asia.

Within a day of the attack, Britain, Canada, Australia, New Zealand, the Netherlands as well as London based Free French and Yugoslavian governments-in-exile and several South American countries and, of course, the United States had all declared war on Japan. Perhaps significantly, President Roosevelt did not ask Congress for a declaration of war against either Germany or Italy on December 8th. So, for three days, there were actually two separate great power wars being fought in the world. On December 11th, Germany and Italy declared war on the United States. All the great powers were now at war.

Originally published in "World War II" at Suite101.com on May 1, 2000.
Revised edition published in "Articles On War" at OnWar.com on July 1, 2003.

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http://www.onwar.com/articles/0005.htm