Former Senator (R-NH)
Senator (R-MO)
Former Assistant Secretary of State for East Asian and Pacific Affairs
Former Secretary of Defense
Senator (R-TX)
Ambassador and former Under Secretary of State for Democracy and Global Affairs
Former Under Secretary of Defense for Policy
Former Senator (R-TN)
Former Secretary of Defense
Former Assistant to the President on National Security Affairs
Former 33rd Commandant of the U.S. Marine Corps
Former Secretary of State
Former Secretary of the Navy
Former Senator (D-CT)
Former Deputy Secretary of Defense
Senator (R-AZ)
Former Senator (D-GA)
Former Secretary of the Air Force
Former Secretary of State
Senator (R-FL)
Former Secretary of State
Former Ambassador to the European Union
Former Deputy Secretary of State
Senator (R-SD)