The Battle of Midway is widely regarded as the most important naval battle of the Pacific Campaign of World War II. Between 4 and 7 June 1942, approximately one month after the Battle of the Coral Sea and six months after Japan's attack on Pearl Harbor, the United States Navy decisively defeated an Imperial Japanese Navy (IJN) attack against Midway Atoll, inflicting irreparable damage on the Japanese fleet. Four Japanese aircraft carriers and a heavy cruiser were sunk for a cost of one American aircraft carrier and a destroyer. After Midway, and the exhausting attrition of the Solomon Islands campaign, Japan's shipbuilding and pilot training programs were unable to keep pace in replacing their losses while the U.S. steadily increased its output in both areas.