FILE – U.S. Ambassador Susan Rice speaks at a news conference after the U.N. Security Council held an emergency meeting on North Korea’s nuclear test on Tuesday morning at U.N. headquarters, in this Feb. 12, 2013 file photo. A White House official said Wednesday June 5, 2013 Tom Donilon is resigning as President Barack Obama’s national security adviser and will be replaced by Susan Rice. (AP Photo/Craig Ruttle, File)