Carter was deputy secretary from October 2011 to December 2013. His profile was boosted by his contributions in planning the raid that killed Osama bin Laden, AP reports. Under the Clinton administration, Carter was the assistant secretary for international security policy.
Other candidates are also being considered, officials said. The list has narrowed—former Pentagon general counsel Jeh Johnson, currently secretary of Homeland Security, is no longer being considered, administration sources told NBC. Johnson was considered too controversial due to his involvement in Obama's immigration policy. Michele Flournoy, former undersecretary of Defense, requested to be withdrawn from consideration.
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Many experts say the position is difficult to fill due to timing. In the final two years of the Obama administration, the defense secretary must address the growing threat from ISIS in Syria and Iraq and the difficulties associated with pulling out from Afghanistan amid tightening budgets.