Hagel Bids Farewell to U.S. Ambassador to NATO U.S. Ambassador to NATO Douglas E. Lute bids farewells to U.S. Defense Secretary Chuck Hagel as he departs the NATO defense ministerial meeting in Brussels, Feb. 27, 2014. SHARE IMAGE: Download Image: Full Size (0.07 MB) Photo By: VIRIN: 504768-J-YOV80-848.jpg Photo Gallery