On June 4, 1942, the Imperial Japanese Navy deployed its main carrier force, the Kido Butai, against Midway Atoll with the objective of provoking a decisive battle and eliminating the last American carriers in the Pacific. Vice Admiral Chuichi Nagumo was unaware that Commander Joseph Rochefort and his cryptanalysis team at Station HYPO had broken the Japanese naval code JN-25, revealing the date, target, and course of attack. Admiral Chester W. Nimitz positioned his three carriers in ambush position northeast of the atoll.

On the morning of June 4, a series of decisions progressively compromised Japan's offensive capabilities. A double rearmament, ordered and then counter-ordered, left the hangars of the Akagi, Kaga, Soryu, and Hiryu crammed with unprotected fuel and ammunition. Three squadrons of American torpedo bombers were destroyed without scoring a single hit, but they dragged Japanese fighter cover down to sea level. At that moment, dive bombers from VB-6 and VB-3 squadrons swooped down from 6,000 meters and, in just six minutes, disabled three aircraft carriers. The Hiryu was destroyed hours later.

The toll was decisive: Japan lost four aircraft carriers, the heavy cruiser Mikuma, and more than 3,000 crew members, including irreplaceable maintenance technicians. The United States lost the Yorktown, the destroyer Hammann, and 307 combatants. From June 4, 1942, Japan relinquished the strategic initiative in the Pacific, paving the way for the first Allied offensive on Guadalcanal.