Attack on Pearl Harbor was a surprise military strike conducted by the Imperial Japanese Navy against the United States naval base at Pearl Harbor, Hawaii, on the morning of December 7, 1941. The sneak attack sparked outrage in the American populace, news media, government and the world. On December 8, President Franklin D. Roosevelt addressed the American Congress, and the nation, to detail the attack. The attack took place before any formal declaration of war was made by Japan, but this was not Admiral Yamamoto’s intention which he thought that the attack should not commence until thirty minutes after Japan had informed the United States that peace negotiations were at an end. It was intended to neutralize the U.S. Pacific Fleet, and hence protect Japan’s advance into Malaya and the Dutch East Indies, where it sought access to natural resources such as oil and rubber.
It was also an action in order to keep the U.S. Pacific Fleet from interfering with military actions the Empire of Japan was planning in Southeast Asia against overseas territories of the United Kingdom, the Netherlands, and the United States. The base was attacked by Japanese fighters, bombers and torpedo planes in two waves, launched from six aircraft carriers. All eight U.S. Navy battleships were damaged, with four being sunk; which two were raised, and with four repaired, six battleships returned to service later in the war. There were 188 U.S. aircraft that was destroyed; 2,402 Americans were killed and 1,282 wounded, and Japanese losses were light: 29 aircraft and five midget submarines lost, and 65 servicemen killed or wounded.
The attack came as a profound shock to the American people and led directly to the American entry into World War II in both the Pacific and European theaters and the next day United States declared war on Japan. The attack had several major aims which were it intended to destroy important American fleet units, thereby preventing the Pacific Fleet from interfering with Japanese conquest of the Dutch East Indies and Malaya, it was hoped to buy time for Japan to consolidate its position and increase its naval strength before shipbuilding authorized by the 1940 Vinson-Walsh Act erased any chance of victory, and it was meant to deliver a severe blow to American morale, one which would discourage Americans from committing to a war extending into the western Pacific Ocean and Dutch East Indies.
To maximize the effect on morale, battleships were chosen as the main targets, since they were the prestige ships of any navy at the time and the main intention was to enable Japan to conquer Southeast Asia without interference. On November 26, 1941, a Japanese task force, of six aircraft carriers departed northern Japan route to a position northwest of Hawaii, intending to launch its aircraft to attack Pearl Harbor. 408 aircraft were intended to be used: 360 for the two attack waves, 48 on defensive combat air patrol including nine fighters from the first wave. Before the attack commenced, two reconnaissance aircraft launched from cruisers were sent to scout over Oahu and report on enemy fleet composition and location.
Another four scout planes patrolled the area between the Japanese carrier force and Niihau, so they could prevent the task force from being caught by a surprise counterattack. At 6:00 a.m. on 7 December, the six Japanese carriers launched a first wave of 181 planes composed of torpedo bombers, dive bombers, horizontal bombers and fighters. The first wave approached land, and one at least radioed a somewhat incoherent warning and other signs were ships off the harbor entrance were still being processed or awaiting confirmation when the attacking planes began bombing and strafing.
The second wave consisted of 171 planes and 90 minutes after it began, the attack was over 2,386 Americans died and 1,139 wounded there were 18 ships that sunk or run aground, including five battleships. Several Japanese junior officers urged Nagumo to carry out a third strike in order to destroy as much of Pearl Harbor’s fuel and torpedo storage, maintenance, and dry dock facilities as possible; and the captains of the other five carriers in the formation reported they were willing and ready to carry out a third strike.