Turkish President Recep Tayyip Erdogan and Iran's President Hassan Rouhani review the honor guard during official welcoming ceremony at Saadabad Palace in Tehran, Iran on April 7, 2015. (Anadolu Agency/Getty Images)
U.S. Assistant Secretary of Defense for Indo-Pacific Security Affairs Randall G. Schriver speaks to reporters on the 2019 Report on Military and Security Developments in China at the Pentagon, Washington, D.C., May 3, 2019. (DoD photo by Army Sgt. Amber I
Chinese rocket launchers are seen at a parade to celebrate the 70th Anniversary of the founding of the People's Republic of China in 1949 , at Tiananmen Square on October 1, 2019 in Beijing, China. (Kevin Frayer/Getty Images)
A handout photo provided by Dong-A Ilbo of North Korean leader Kim Jong Un and U.S. President Donald Trump inside the demilitarized zone (DMZ) separating the South and North Korea on June 30, 2019. (Dong-A Ilbo/Getty Images)