The U.S. has opened the door to parking a ballistic missile defense system on North Korea's doorstep, a move that could reshape North Asia's security landscape.
Kim Jong Un's launch Sunday of a long-range rocket prompted a reaction that his nuclear test last month did not: South Korea now says it will consider allowing the deployment on its soil of a U.S. Army system known as THAAD.
For years South Korea has danced around the idea of Terminal High Altitude Area Defense, which targets missiles in flight and could complement lower-altitude defenses already in the country. That is mainly because it risks annoying neighbor China, which has warned against THAAD being deployed on the Korean Peninsula. It could also spur Japan to look at using it.