Private First Class Whitmore was a member of Company C, 1st Battalion, 7th Marines, 1st Marine Division. He was Killed in Action while fighting the enemy at the Western Outposts in Korea on 27 October 1952.

Whitmore 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.