Activated as the 26th Pursuit Squadron at Hamilton Field, California in January 1941 as a Curtiss P-40 Warhawk pursuit squadron to defend the West Coast. Deployed to the China-Burma-India Theater in March 1942, initially arriving at Karachi, India moving via Australia and Ceylon. It was assigned to Tenth Air Force. The squadron defended the Indian terminus of the Hump airlift route over the Himalayas between India and China and airfields in that area, operating from the Assam Valley of northeast India. The squadron flew strafing, bombing, reconnaissance, and patrol missions in support of Allied ground troops during a Japanese offensive in northern Burma in 1943.