Acting U.S. Secretary of Defense Patrick Shanahan speaks during his meeting with his Portuguese counterpart, João Gomes Cravinho, at the Pentagon in Washington on June 14.
Then-Marine Corps Lt. Gen. Kenneth McKenzie, nominee to be general and commander of the U.S. Central Command, testifies during a Senate Armed Service Committee confirmation hearing on Capitol Hill in Washington on Dec. 4, 2018.
Guy Roberts testifies before the Senate Armed Services Committee during his confirmation hearing to be assistant defense secretary for nuclear, chemical, and biological defense programs in the Dirksen Senate Office Building in Washington on Nov. 2, 2017.
US President Donald Trump, First Lady Melania Trump, Poland's President Andrzej Duda and his wife Agata Kornhauser-Duda watch as an F-35 fighter planes flies over the White House on June 12, 2019, in Washington DC. (Photo by MANDEL NGAN / AFP) (Photo credit should read MANDEL NGAN/AFP/Getty Images)
The Virginia-class fast-attack submarine USS Hawaii prepared to moor at the historic submarine piers at Joint Base Pearl Harbor-Hickam on June 6. Each Virginia-class submarine uses nearly five tons of rare-earth materials.
A Lockheed Martin crew chief signals to the F-35A Lightning II pilot that chocks have been placed, Feb. 4, 2019 at Luke Air Force Base, Ariz. (U.S. Air Force photo by Airman 1st Class Aspen Reid)
Russian S-400 air defence missile systems roll at Red Square during the Victory Day military parade in Moscow on May 9, 2016. (KIRILL KUDRYAVTSEV/AFP/Getty Images)
President Donald Trump shows off posters as he talks with Crown Prince Mohammad bin Salman of the Kingdom of Saudi Arabia during a meeting in the Oval Office at the White House on Tuesday, March 20, 2018 in Washington, DC. (Photo by Jabin Botsford/The Washington Post via Getty Images)
Acting U.S. Secretary of Defense Patrick Shanahan, left, gestures as International Institute for Strategic Studies CEO John Chipman looks on in Singapore on June 1.
