On June 5, South Korean President Moon Jai-in ordered an environmental impact assessment in the area where four additional Terminal High Altitude Area Defense (THAAD) launchers were to be deployed. THAAD is a mobile system capable of hitting ballistic missiles inside or outside the atmosphere in their final, or terminal, phase. The unexpected move has caused alarm for policy makers in Washington, DC, who are worried about Beijing’s influence on the newly elected president.