William "Bill" Daniel Ehrhart is an American poet, writer, scholar, and Vietnam veteran. He received the Purple Heart Medal and the Navy Combat Action Ribbon for his service in Vietnam. He holds a PhD from the University of Wales at Swansea. Ehrhart has been called "the dean of Vietnam war poetry" and is the author of more than 30 books, including Vietnam Perkasie: A Combat Marine Memoir, Passing Time: Memoir of a Vietnam Veteran Against the War, Busted: A Vietnam Veteran in Nixon's America, and Thank You for Your Service: Collected Poems. His most recent book is What We Can and Can't Afford: Essays on Vietnam, Patriotism, and American Life(McFarland, 2023).