Soldiers from 1st Stryker Brigade, 1st Armored Division operate vehicles equipped with Warfighter Information Tactical Increment 2 at Fort Bliss, Tx. October, 2014 (U.S. Army)
Secretary of Defense James Mattis talks with South Korean Defense Minister Song Young-moo in the Demilitarized Zone on October 27. (Jeon Heon-Kyun-Pool/Getty Images)
Defense Secretary James Mattis and Chairman of the Joint Chiefs Gen. Joseph Dunford greet House Armed Services Committee Chairman Mac Thornberry (R-TX) on June 12, 2017. (Chip Somodevilla/Getty Images)
President Donald Trump and Russian President Vladimir Putin wave at the Asia-Pacific Economic Cooperation Summit in Vietnam on November 10. (Mikhail Klimentyev/AFP/Getty Images)
President Donald Trump and first lady Melania Trump exit Air Force One upon their arrival at Beijing on November 8. (Photo by Lintao Zhang/Getty Images)
South Korean President Moon Jae-In shakes hands with President Donald Trump during their summit in Seoul on November 7. (Jeon Heon-Kyun - Pool /Getty Images)