[2] On August 7, 1917, after the United States joined World War I, he left Harvard, where he was a sophomore, to enlist as an aviation cadet, and was assigned to ground training at the School of Military Aeronautics at Cornell University.

Upon his graduation on October 13, 1917, he was transferred to the Aeronautical General Supply Depot and Concentration Barracks at Hazelhurst Field, Garden City, New York, and assigned to the foreign service detachment to complete his flight training overseas.

Hamilton served in the Air Service as an instructor in aerial navigation, meteorology, astronomy and officer-in-charge of bombing instruction at Ellington Field.

[3] A month later he was appointed Assistant Chief of Staff (G-2) of Maj. Gen. Lucian K. Truscott's Force Goalpost, conducting the assault on western French Morocco.

After landing on Green Beach before dawn, still under hostile fire from shore batteries, the officers commandeered a small truck and were strafed by French aircraft when it became stuck in a muddy marsh.

After the truck was extricated by a detachment of combat engineers, they attempted to continue their mission but were forced to return to the beach when caught in the exchanges of French artillery and naval gunfire from Task Group 34.8 of the United States Navy.

After several contacts with French troops to obtain directions, and requesting a guide (which was refused), the jeep proceeded cautiously approximately six miles into Port Lyautey.

As they came over a rise on the outskirts near the French headquarters, a hidden machine gun position took them under sustained fire and killed Craw.

The local commander, Col. Charles Petit, declined to order a cease-fire but agreed to forward Hamilton's message to his immediate superior, Major General Maurice Mathenet.

Fearful of the possible consequences for killing an officer traveling under a flag of truce, the French refused to allow Hamilton to communicate with his headquarters and kept him under "house arrest.

[9] In December 1942 Hamilton became Intelligence and Air Officer for the North African Theater Advanced Headquarters at Algiers and was promoted to lieutenant colonel.

After the AAF became the United States Air Force, Hamilton was assigned to Headquarters USAF in the Office of Director of Plans and Operations.

Driven away from the mouth of the Sebou River by heavy shelling from all sides, the landing boat was finally beached at Mehdia Plage despite continuous machinegun fire from three low-flying hostile planes.