TAMPA, Fla. — Life can be harsh for those living homeless on the nation's city streets. But for one man, it's even worse – especially when he deals with the emotional scars of battle.

Polls show that 15 percent of the U.S. homeless population have served in the military. Many suffer from Post-Traumatic Stress Disorder (PTSD).

"It was definitely rough when I came home from the war in 1978," says Richard McAdams, a veteran who served in the Marines during the Vietnam war. "I got off the plane and they were spitting on me and calling me baby-killer."

McAdams says he served in Vietnam from 1969 to 1978, although the war officially ended three years prior.

"Well I don't exactly remember the year," he says, "but I know that it was really hell over there, especially when the Chosin was so freezing cold. My friend Billy actually lost his fingers to frostbite."