Technical Sergeant Keegan was a crew member of a F4U Corsair fighter with the Marine Fighter Squadron 513, Marine Air Group 33, 1st Marine Air Wing. He died in Korea from other causes on 19 January 1951.

Keegan was awarded the Purple Heart, the Combat Action Ribbon, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.