** FILE ** President Obama listens as then-U.N. Ambassador Susan Rice, his choice to be his next National Security Adviser, speaks in the Rose Garden at the White House in Washington on June 5, 2013, where the president made the announcement. Samantha Power, his nominee to replace Rice, is at left. (Associated Press)

Photo by: Charles Dharapak

** FILE ** President Obama listens as then-U.N. Ambassador Susan Rice, his choice to be his next National Security Adviser, speaks in the Rose Garden at the White House in Washington on June 5, 2013, where the president made the announcement. Samantha Power, his nominee to replace Rice, is at left. (Associated Press)