Private First Class McAlpine was a member of the 31st Infantry Regiment, 7th Infantry Division. He was taken Prisoner of War while fighting the enemy in North Korea on 1 December 1950 and died while a prisoner on 30 October 1952.

McAlpine was awarded the Purple Heart, the Purple Heart, the Combat Infantryman's Badge, 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.