This story is part of American Anthem, a yearlong series on songs that rouse, unite, celebrate and call to action. Find more at NPR.org/Anthem.
It was February 1967, and 18-year-old Marine Pfc. Bill Ehrhart was days away from leaving for Vietnam. He had just enjoyed his last weekend off base, and his friends had offered to drive him back to Camp Pendleton, Calif., before sunrise.
"It was goodbye civilian world, next stop Vietnam," says Ehrhart, now a writer and poet.