Nationalistic and militaristic fervor in Imperial Japan and a strong belief in Japan's destiny and divine right to rule all of Southeast Asia brought Japan and the United States into increasing diplomatic confrontation throughout the 1930s. Compounding the matter was a bloody undeclared war the Japanese were waging in China and the weakening of European control in Asian colonies as a result of the Second World War. The signing of the Tripartite Pact in September 1940, which allied Japan with Germany and Italy, aggravated tensions between the United States and Japan as the latter nation joined the Axis Powers. When Japan seized a major portion of Southeast Asia under agreement with Vichy France, the administration of President Franklin D. Roosevelt was moved to action. Already outraged by Japanese aggression in China, the Roosevelt administration introduced economic sanctions to make its point clear: The United States would not facilitate Japan's expansion into the Pacific, just as it opposed German expansion in Europe. An American embargo cut off shipments of scrap steel, raw materials, oil and high-octane gasoline, while freezing Japanese financial assets in the United States. The Japanese, having only a six-month supply of strategic fuel available for its armed forces, felt the only choice was to initiate the conquest of Southeast Asia, which meant in evitable war with America, Britain, and the Netherlands. Japan had seen the United States expand its naval authority in the Pacific in the late 1930s. The bolstering of defenses in the Philippines, Hawaii, Guam, Midway and Wake Island, as well as stationing the United States Pacific Fleet at Pearl Harbor, made America the first priority for a Japanese attack.
Fearing that the U.S. Pacific Fleet would pose a formidable obstacle to Japanese conquest of Southeast Asia, Admiral Isoruko Yamamoto, the commander in chief of the Japanese Combined Fleet, visualized a bold attack on the Pacific Fleet while it lay at anchor at Pearl Harbor. Such a "surprise strategical" attack, bold and daring in its execution, would secure the Pacific and initiate the war, following in the tradition of the Japanese naval victory over the Russians at Port Arthur in 1904 and the opening maneuvers in Japan's invasion of China. Although nationalistic and militaristic pride was driving Japan inexorably toward war with the United States, some military leaders were concerned about the long-range implications of a protracted war with an industrial giant. Yamamoto expressed doubt, apprehension and disgust over Japan's headlong push toward conflict. In January 1941 he wrote to Ryoichi Sasakawa, who was the president of Japan's rightist nationalistic organization Kokusai Domei and one of Yamamoto's staunch supporters:
... if there should be a war between Japan and America, then our aim, of course, ought not to be Guam or the Philippines, nor Hawaii or Hong Kong, but a capitulation at the White House, in Washington itself. I wonder whether the politicians of the day really have the willingness to make sacrifices, and the confidence, that this would entail? (Agawa 1979:291)
Thus the admiral who was about to initiate the opening attack of the war revealed his personal attitude. Although he was reluctant to push toward war, he possessed a strong sense of duty. With Japanese policy indicating that war was now inevitable, Yamamoto took a hard look at the navy and Japan's chances, noting he expected to "run wild" for six months, with the outcome after that up in the air. In order to hit U.S. forces so hard that America would seek a quick peace, Yamamoto explained to Navy Minster Koshiro Oikawa, "We should do our very best.., to decide the fate of the war on the very first day." He described his operational plan to attack Pearl Harbor.
The plan had been mentioned before. In the spring of 1940 Japan's air fleet had conducted aerial torpedo exercises under the watchful eyes of Yamamoto and Rear Admiral Shigeru Fukudome, head of the first division of the naval general staff. In passing conversation, almost in a whisper, Yamamoto had said, "I wonder if an aerial attack can't be made at Pearl Harbor?" (Prange 1981:14). Even then, the thought was not new. Exercises by both countries had played out such a scenario, but both Japan and the United States believed an aerial torpedo attack on Pearl Harbor was impossible. The actual plan of operation, formulated by a young tactical genius in aerial warfare, Commander Minoru Genda, was agreed to after months of internal dissension among the ranks of command in the Japanese navy. When negotiations with the United States were deemed unsatisfactory to the Japanese government of Prime Minister Hideki Tojo, official blessing was sought for the "Hawaii Operation." It was given on September 6, 1941, at an Imperial Conference. Japan was committed to war.
The First Air Fleet had held maneuvers for almost a year, and the results were promising. Under the direction of Commander Mitsuo Fuchida, who would lead the air assault on Pearl Harbor, the "impossible" task of an aerial torpedo attack was made possible. Conventional aerial torpedoes plunged to more than 100 feet in depth and ran a long distance to arm. The 45-foot average depth of Pearl Harbor and the short runs necessary to sink ships there were dealt with by adding wooden fins to the torpedoes, altering the arming devices, and by training in simulated conditions.
A task force of 32 vessels -- particularly the carriers AKAGI, HIRYU, SORYU, KAGA, ZUIKAKU and SHOKAKU --was dubbed the "Kido Butai" (Strike Force). Secretly assembling on Tankan Bay in Northern Japan, the force was placed under the direct command of Vice Admiral Chuichi Nagumo. At 6:00 a.m. on November 26, 1941, the Japanese fleet weighed anchor and slipped out to sea for Hawaii. In planning the operation, the northern approach to Hawaii had been selected even though the weather and seas would be rough. The winter storms would mask the Japanese fleet and lessen the chances of encountering the enemy while on the high seas. A screening force of submarines traveled 200 miles ahead, and as the fleet approached Hawaii, it received up-to-date reports from agents on Oahu as well as the submarines, which finally were picketed around the islands. On December 2 a coded message arrived in Tokyo: "Climb Mt. Nitaka." This pre-arranged message signaled the final decision to wage war. The fleet was to press forward and attack on Sunday, December 7, 1941, Hawaii time.
At 6:00 a.m. on December 7 the Japanese fleet was 230 miles north of Oahu. Six carriers turned into the wind and launched the first wave -- 183 planes. At the launching, two Zero fighters dropped from the mission: One crashed into the sea on takeoff, another developed engine trouble and was left on board the carrier. At 6:20 Commander Fuchida led the first wave of planes toward Pearl Harbor.
As soon as the first wave departed, the carrier crews readied the second wave. At 7:05 the carriers again swung eastward into the wind and began launching 167 aircraft. As before, the first lift-offs were the Nakajima B5 N2 "Kates," which served as torpedo bombers on the first wave, and as horizontal bombers on the first and second waves. The Kates were followed by the Aichi D3A1 "Vals" (dive bombers) and Mitsubishi A6M2 Reisen Zero fighters. Only one dive bomber from the HIRYU developed engine trouble and failed to make the trip, leaving 350 planes in the air.
Meanwhile on Oahu, two warnings of the impending attack occurred. In the waters just outside the entrance to Pearl Harbor, the destroyer WARD at 6:30 a.m. fired on, depth-charged and sank a submarine within the defensive sea area. Bureaucratic delays and the need for confirmation caused an hour to go by before the report was forwarded to Admiral Husband E. Kimmel, commander in chief of the U.S. Pacific Fleet.
The second warning occurred at 7:02 a.m., nearly half an hour after the WARD fired the first shot of America's Pacific War. Two Army radar operators at the Opana station above Kahuku Point on Oahu's north shore picked up a large formation of planes on their radar screens. After checking and rechecking equipment, they notified the watch officer at Fort Shafter. No action was taken because the officer believed the planes to be a flight of B-17s flying in from California.
Flying through thick cloud cover, Commander Fuchida thought for a moment he had overflown Oahu, but a sudden parting of the clouds revealed the island's north shore. The signal was given to assume attack formation. As Fuchida looked toward Pearl Harbor and the surrounding airfields, he was relieved to see that the attack was a surprise, and the earlier report of Kido Butai's scout plane "Enemy fleet in port!" was accurate. To Fuchida's disappointment, the prime targets of the attack -- the aircraft carriers -- were absent. Changing their plan, the torpedo planes concentrated on the battleships lined up along Battleship Row and the east side of Ford Island.
With assignments memorized by constant training, the first wave of planes attacked at 7:55 a.m. At about the same time, fighters and dive bombers hit the airfields at Kaneohe, Hickam, Ewa, Bellows and Wheeler. Within two hours, most American air power in Hawaii was destroyed.
At Pearl Harbor, as morning colors were readied and sailors and civilians ate breakfast, the Japanese planes struck. In 15 minutes the main battle line of the Pacific fleet was neutralized. The battleships CALIFORNIA, OKLAHOMA, WEST VIRGINIA, NEVADA and ARIZONA were sunk, as was the old battleship UTAH then being used as a target and antiaircraft training vessel. The battleships MARYLAND, TENNESSEE and PENNSYLVANIA were damaged. Initially, the American response to the attack was sporadic, but within five minutes American vessels began to fire back in earnest against the attackers. "Air Raid Pearl Harbor, this is no drill!" was relayed to the fleet.
The assault of the first wave ended about 8:45 a.m. There was a momentary lull before the second wave of Japanese planes arrived at 8:50 a.m. No torpedo planes came with the second group of dive and high-altitude bombers.
As the second wave withdrew, Fuchida circled Pearl Harbor and assessed the damage. Satisfied, he took a last look and signaled his pilots to return to the carrier. The main objective of the attack -- demobilizing the Pacific Fleet -- had been accomplished. More than 2,400 Americans were killed and 1,104 wounded. Twenty-one ships of the Pacific Fleet had been sunk or damaged, and 75 percent of the planes on the airfields surrounding Pearl Harbor were damaged or destroyed.
It was nearly 10 o'clock when the first wave of Japanese aircraft began landing on their carriers. By noon, the last planes had been recovered. Twenty-nine Japanese planes were lost, along with 55 airmen. The Special Attack Unit of midget submarines had lost 10 crewmen and all five boats, one boat and one prisoner were captured by Americans the following day on the beaches near Bellows Airfield.
Fuchida was gratified to see planes being readied for a third assault because many targets had been left untouched, particularly the naval shipyard, oil-storage facilities, and a number of American ships. While he wondered when the third wave would be launched, a heated debate was underway on the bridge of the fleet flagship HIJMS AKAGI.
Admiral Nagumo had feared the operation would not be successful, yet he had achieved successful results with minimal casualties. It was his contention that the mission was accomplished. Furthermore, the fleet's fuel was running low. More important, American carriers and other ships not in port were now searching for him. At 1 o'clock the task force altered course and began its journey back to Japan. This decision was a major blunder that greatly minimized the long-term effects of the attack on the American war machine.
Excerpt from the Submerged Cultural Resources Study: USS Arizona and Pearl Harbor National Historic Landmark