 In 1928, his final year at Leavenworth, Middleton received orders to attend the Army War College in Washington, D.C .. His year at this highest level of professional military education was very fulfilling. He spent time in the school library and the Library of Congress. He wrote his staff memorandum (equivalent to a thesis) on the subject of Army transportation. Recalling his personal experience with horses and mules in France, he recommended that motorized transport significantly replace the Army's use of livestock. The commandant of the school commended Middleton for work of exceptional merit, and sent his ideas to the highest levels in the War Department.
