World War II Remembered: The Battle of Midway - Part 2
By Jennifer King and Timothy Rollins
June 12, 2002

Dateline: 4-7 June 1942
The Battle of Midway
Pacific Theater of Operations

Admiral Isoroku Yamamoto's battle plan consisted of three elements: first, the occupation of the Western Aleutians; second, occupation of Midway and third, fleet engagement. Admiral Yamamoto counted on the Aleutian force diverting Nimitz, deceiving him as to the actual Japanese goal. Yamamoto did not foresee Nimitz arriving at Midway until after his occupation force had seized the island and he was in firm control.

Admiral Yamamoto's plan suffered from the typical Japanese defect of being far too complex and intricate - it also required that the enemy behave in exactly the fashion expected. Admiral Yamamoto, however, didn't know about "America's secret weapon" - to be found in a dank basement located in Pearl Harbor known as "Station Hypo", manned by a disheveled genius named Joseph Rochefort.

Rochefort, known for padding about in a wrinkled uniform, unknotted bathrobe and bedroom slippers, had taken the spring of 1942 and molded his group of cryptographers into a crack force. By 8 May, Rochefort had deduced that a major Japanese offensive was afoot. He almost immediately pegged the target as Midway, but the Washington brass was not convinced. Rochefort and his able aide, Lt. Commander Jasper Holmes, USN, hit upon a ruse in order to prove the target.

Holmes had been to Midway, and knew that there was no natural freshwater supply on the island. The station depended upon a seawater evaporator/condenser for most of its freshwater. Also pertinent was the half-century old cable wire laid in 1903. Most communications between Midway and Pearl depended upon this, and the Japanese were not able to intercept these wires. This gave the Americans yet another advantage.

Holmes and Rochefort came up with an able deception. Midway proper was notified, via secure cable, to broadcast a message that their evaporator/condenser had broken down and that fresh water was therefore scarce. This message was dutifully sent. Another was also sent, via communications which were known to have been breached by Japanese Intelligence.

Shortly thereafter, a communication was decoded through usage of the broken Japanese code. Target "AF", which had garnered much Japanese coverage over the past several months, was bereft of "its saltwater condenser". Enemy invasion ships would have to carry more water supplies as a result.

Midway Island had been successfully detected as the target. What Admiral Nimitz and Admiral Yamamoto would subsequently do, would result in turning the direction of the entire war in the Pacific. ***

ADDITIONAL BACKGROUND INFORMATION:

Admiral Yamamoto commanded the Combined Fleet before the outbreak of the Pacific War and during its first sixteen months. He was responsible for planning the Attack on Pearl Harbor and most other major operations during this time. His scheme for eliminating the U.S. fleet as a major opponent led to the June 1942 Battle of Midway, in which the Japan lost naval superiority in the Pacific.

Despite Midway's adverse outcome, Yamamoto continued as Combined Fleet commander through the following Guadalcanal Campaign, which further depleted Japan's naval resources. While on an inspection tour in the Northern Solomon Islands, he was killed in an aerial ambush by U.S. Army Air Force planes on 18 April 1943. Isoroku Yamamoto was posthumously promoted to the rank of Admiral of the Fleet.