POHANG, SOUTH KOREA - JULY 06: U.S. Marines from 3rd Marine Expeditionary force deployed from Okinawa, Japan, participate in the joint combat training with South Korean soldiers on July 6, 2016 in Pohang, South Korea. The Korean peninsula is the world's last Cold War frontier as stalinist North Korea and pro-western South Korea have been technically at war since the 1950-53 conflict. (Photo by Chung Sung-Jun/Getty Images)
