For a Kentucky rifleman who spent his tour trudging through Vietnam's Central Highlands, it was Nancy Sinatra's "These Boots Are Made for Walkin'." For a "tunnel rat" who blew smoke into the Viet Cong's underground tunnels, it was Jimi Hendrix's "Purple Haze." For a black marine distraught over the assassination of Martin Luther King Jr., it was Aretha Franklin's "Chain of Fools." And for countless other Vietnam vets, it was "I Feel Like I'm Fixin'...