Defense Secretary Chuck Hagel briefs reporters at the Pentagon on Monday. Hagel and President Obama will need to fight through a wall of resistance to their proposed defense budget cuts, say former members of a defense base closing commission. Carolyn Kaster/AP hide caption

itoggle caption Carolyn Kaster/AP

Secretary of Defense Chuck Hagel attends the International Institute for Strategic Studies Regional Security Summit in the Bahraini capital Manama on Saturday. Mohammed Al-Shaikh /AFP/Getty Images hide caption

itoggle caption Mohammed Al-Shaikh /AFP/Getty Images

Concerns over China's air defense claims led Secretary of Defense Chuck Hagel to call Japan's defense minister Wednesday. Here, a man makes a call near a replica of a Chinese fighter jet displayed in Beijing Wednesday. Ng Han Guan/AP hide caption

itoggle caption Ng Han Guan/AP

Defense Secretary Chuck Hagel. Chip Somodevilla/Getty Images hide caption

itoggle caption Chip Somodevilla/Getty Images