President Obama's fourth secretary of defense will be sworn in next week.
Ashton Carter is one step closer to becoming secretary of defense.
President Obama has some new weapons in his fight to increase the federal budget.
The Defense Department no longer operates any prisons in Afghanistan.
Meet the new secretary of defense.
The former deputy defense secretary has reportedly been picked to lead the Pentagon.
Inside the search for a new defense secretary.
Hagel's resignation from the Pentagon will make him the third defense secretary to resign in the six years of the Obama administration.