May 4

Battle of the Coral Sea Begins — First Carrier Battle in History

American and Japanese carrier forces began the first naval battle in history fought entirely by aircraft — neither fleet's surface ships came within sight of the other. Both sides launched air strikes against the opposing carrier groups.

Though a tactical Japanese victory, the Coral Sea battle stopped Japan's invasion of Port Moresby and removed two Japanese carriers from the Battle of Midway, contributing to Japan's decisive defeat a month later.