In May 1942 Collins was appointed as battalion commander of the 1st Battalion, 130th Infantry Regiment. In May 1944 the 130th Infantry deployed to Finschhafen in New Guinea. In August 1944 Collins assumed command of the 130th Infantry, commanding the regiment during the Battle of Morotai and Battle of Luzon, where the 130th Infantry participated in the capture of Baguio. The 130th Infantry then participated in the Occupation of Japan, landing there in September 1945.