The Battle of Coral Sea took place on May 4-8, 1942 in the Pacific between the US and Japan. The battle was notable for two reasons. Firstly, the Japanese advance, unbroken since Pearl Harbor, had been blunted. Secondly, this was the first naval battle where the ships never came into visual range of each other.

The Japanese, at the height of their expansion after the attack on Pearl Harbor, sought to strengthen their defensive perimeter by seizing Port Moresby, New Guinea. From there the Japanese would be within striking range of Australia, and threaten the shipping supply lanes between the US and Australia.The Japanese invasion fleet, which included 2 heavy and 1 light aircraft carriers were met by an American fleet that include 2 heavy aircraft carriers. In the ensuing battle the Japanese lost 1 light carrier and suffered damage to 1 heavy carrier. The Americans lost 1 heavy carrier and suffered damage to 1 heavy carrier. This was technically a Japanese tactical victory, but they were forced to turn back as they lost too many aircraft in the battle.

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