The very complex Japanese Navy plan for the Midway and Aleutian operations required careful cooperation by five separate groups of warships, and precise coordination of ship movements over a very large area of the Pacific Ocean stretching from Alaska to the central Pacific. All of this had to be achieved while maintaining strict radio silence. A huge fleet of about 200 Japanese warships, transports, and oilers was assembled for the Midway and Aleutian offensives. It included eleven battleships, five large fleet aircraft carriers, three light aircraft carriers, twenty-three cruisers, sixty-seven destroyers, and twenty-two submarines. The Japanese fleet was divided into five main commands: Main Force (Admiral Isoroku Yamamoto, aboard the giant battleship Yamato ), First Carrier Striking Force, or Kido Butai, (Vice Admiral Chuichi Nagumo, who led the carrier attack on Pearl Harbor), Midway Invasion Force (Vice Admiral Nobutake Kondo), Northern Aleutians Force, and the Advance Submarine Force.
Rear Admiral Frank J. Fletcher was the commander of the American carrier task forces at the vital battles of Coral Sea and Midway. As senior tactical commander, he played an important part in securing Allied victories in both battles. In an extraordinary act of patriotism and generosity, he passed overall command of the American carrier task forces at Midway to Rear Admiral Spruance after his own flagship USS Yorktown had been disabled by Japanese dive bombers and after the Americans had already destroyed three of Japan's most powerful carriers.
The Japanese offensive against America's Aleutian Islands off the western coast of Alaska would take place on 3 June 1942, and was intended by Navy General Staff to provide a northern anchor for Japan's eastern defensive perimeter in the Pacific. Admiral Yamamoto hoped that the Aleutian operation would distract the attention of the United States from Midway Atoll which was the focus of his main attack.
Planning the attack on Midway Atoll
The Japanese had planned that their Midway offensive would take place in three separate phases. In the first phase, the large fleet aircraft carriers of Vice Admiral Chuichi Nagumo's powerful First Carrier Striking Force (Kido Butai ) would approach Midway Atoll from the north-west on 4 June 1942. In the pre-dawn darkness, Nagumo would launch aircraft from his four carriers to attack the American air and land defences on Sand and Eastern Islands. When the American defences on Midway had been neutralised by Nagumo's carrier-launched air attacks, the second phase would begin. Warships and transports of the Midway Invasion Force commanded by Vice Admiral Nobutake Kondo would approach Midway from the south-west and land troops to crush all resistance, occupy the islands, and prepare the airfield to receive Japanese combat aircraft. Having neutralised Midway Atoll and prepared it for Japanese occupation, the third phase required Vice Admiral Nagumo to wait in ambush with his carrier force for the anticipated arrival of carriers of the United States Pacific Fleet on or soon after 6 June. When the American Pacific Fleet arrived from Pearl Harbor to defend Midway, Admiral Nagumo would destroy it. Admiral Yamamoto would hold the powerful battleships of his Main Force in reserve west of Midway to provide any support that Vice Admiral Nagumo might require to destroy the American fleet.
