South Korean protesters pray during a rally to oppose a plan to deploy the advanced U.S. missile defense system called Terminal High-Altitude Area Defense, or THAAD, near U.S. Embassy in Seoul, South Korea, Thursday, April 27, 2017. In a defiant bit of timing, South Korea announced Wednesday that key parts of a contentious U.S. missile defense system had been installed a day after rival North Korea showed off its military power. (AP/RSS Photo/Ahn Young-joon)