4th May 1942 marked the start of the Battle of the Coral Sea, between the Imperial Japanese Navy and U.S.
4th May 1942 marked the start of the Battle of the Coral Sea, between the Imperial Japanese Navy and U.S. and Australian naval forces, in the first-ever naval action in which the opposing fleets neither sighted nor fired upon one another, attacking over the horizon with aircraft carriers instead. By early 1942, the Japanese had made rapid gains in South East Asia. By April, they were also ready to seize control of the Coral Sea, off the northeast coast of Australia, by establishing air bases at Port Moresby, in Papua New Guinea, and at Tulagi, in the Solomon Islands. This would enable them to strengthen their defensive perimeter and to sever lines of communication between Australia and the United States. Accordingly, an invasion force was assembled, while the aircraft carriers Shōkaku and Zuikaku were dispatched to the Coral Sea to provide air cover and to intercept and destroy any Allied naval forces that entered the area. U.S. intelligence intercepted Japanese communications, and as