As academic, Carter would bring different outlook to Pentagon, but policy influence unclear

FILE - In this Feb. 12, 2013 file photo, Ashton Carter testifies on Capitol Hill in Washington. Carter has emerged as President Barack Obama's top candidate to become the next defense secretary, according to administration officials, putting him in line to take over a sprawling department that has had an uneasy relationship with the White House. (AP Photo/J. Scott Applewhite, File) (The Associated Press)

The experiences Ashton Carter would bring to the job of defense secretary are vastly different from Chuck Hagel's in several important ways — starting with the fact that Carter is an academic and a policy wonk.

How Carter would pursue President Barack Obama's defense agenda, or use his influence to bend it in new directions, is less obvious.

Unlike Hagel and every other man who has led the Pentagon over the past 30-plus years, Carter has served neither in the military nor in Congress. Hagel did both. And although he moved in national security circles for years, including his time as head of the Atlantic Council, Hagel was never seen as a master of policy.

Obama plans to announce Carter as his nominee on Friday.