What both Japan and South Korea need right now is assurance from the United States that its alliances are a priority. This frees Defense Secretary Mattis to focus on ensuring readiness and establishing the high levels of security coordination on how to deal with North Korea. But by agreeing to the THAAD deployment, South Korea now faces increased political and economic retaliation from China. China has already applied non-tariff barriers and on-site safety inspections for South Korean businesses operating in the country, and even curtailed concerts by Korean artists and removed Korean dramas from Chinese television. This was all to deter South Korea from deploying THAAD, at the request of the U.S.

Source: Forbes February 01, 2017 23:37 UTC