Fighting in the pacific was mainly fought by which countries?

Fighting in the Pacific was mainly fought by United States and Japan.

There were two theaters of World War II. One theater of World War II was in Europe, the other was in the Pacific. The Pacific theater of war involved Japan, China, Korea, the Philippines, and many more islands and countries in Southeast Asia.

Following the Battle of Midway the United States began to fight back against the Japanese. They fought to take control of strategic islands in the Pacific. One of the first major battles occurred over the island of Guadalcanal.

it made them more prductive and efficent but with the change of polcies less and les got into the navy