The 28-year-old left the country on Tuesday to begin his basic training.

"Today Cooper left to begin his service in the United States Air Force," Cooper's wife, Scarlett, wrote on Instagram. She added, "I'm incredibly proud."

Publicly he announced, "Today I informed leadership and financiers of Stag and Hefner Media Corporation I would be stepping back from focusing on launching a new company and stepping towards greater service to community and country," he wrote on Instagram on Dec. 10. "In a week I depart for US Air Force basic training. A new road ahead."