Photos: Chuck Hagel's military, government career President Barack Obama is nominating Chuck Hagel, a former U.S. senator from Nebraska, to succeed Defense Secretary Leon Panetta. Hagel served in the military during the Vietnam War, leading him later to tell a biographer, "I will do all I can to prevent war." After coming home from Vietnam, Hagel worked briefly as a newscaster, then had a career in business, before entering public service as a Republican senator for 12 years. Here's a look at his military and government career: