Following his service in the U.S.-Mexican War, Hawes became an assistant instructor at the U.S. Military Academy. Among the subjects he taught were infantry tactics, cavalry tactics, and mathematics. In 1850, he studied advanced tactics at the Cavalry School of Saumur, France. On his return to the United States in 1852, Hawes was stationed on the Texas frontier, served in the Utah expedition in 1857 and 1858, and helped put down disturbances in "Bleeding Kansas."