Battle of Midway
Six months after the attack on Pearl Harbor, the United States defeated Japan in one of the most decisive naval battles of World War II. Thanks in part to major advances in code breaking, the United States was able to preempt and counter Japan’s planned ambush of its few remaining aircraft carriers, inflicting permanent damage on the Japanese Navy. An important turning point in the Pacific campaign, the victory allowed the United States and its allies to move into an offensive position.
This fleet engagement between U.S. and Japanese navies in the north-central Pacific Ocean resulted from Japan’s desire to sink the American aircraft carriers that had escaped destruction at Pearl Harbor. Admiral Yamamoto Isoroku, Japanese fleet commander, chose to invade a target relatively close to Pearl Harbor to draw out the American fleet, calculating that when the United States began its counterattack, the Japanese would be prepared to crush them. Instead, an American intelligence breakthrough–the solving of the Japanese fleet codes–enabled Pacific Fleet commander Admiral Chester W. Nimitz to understand the exact Japanese plans. Nimitz placed available U.S. carriers in position to surprise the Japanese moving up for their preparatory air strikes on Midway Island itself.
https://www.history.com/topics/world-war-ii/battle-of-midway
