Bruce Bennett Explains Why South Korea Needs THAAD

RAND researcher Bruce Bennett explains why South Korea needs the THAAD missile defense system:

There were many reasons for the deployment of THAAD in Seongju, the location chosen for the THAAD battery in South Korea. One leading reason: In a major Korean conflict, tens of thousands of U.S. military personnel would deploy to Korea over time largely through the Pusan port area in southeastern Korea. They would be most vulnerable to a North Korean nuclear weapon attack while in the port area and while assembling to depart from Pusan. Not protecting exposed military personnel from the North Korean ballistic missile and nuclear weapon threat would be irresponsible, the United States concluded.

By placing THAAD in Seongju, the U.S. can also attempt to protect the large South Korean urban areas of Pusan, Kwangju, Pohang, and Daegu, as well as many other cities in the southern part of South Korea. During a U.S. military deployment to protect South Korea, a North Korean nuclear weapon detonating on Pusan might kill thousands of U.S. military personnel arriving in Pusan, but it could also kill a 100,000 or so South Koreans. With this THAAD placement, the United States is trying to prevent such an outcome.  [Korea Times]

You can read more at the link, but one of the arguments often used by anti-THAAD activists is that the system is there to protect US troops not Koreans.  This argument has always been one of the stupidest considering that if a missile with a nuclear weapon is fired at a US military base the explosion and destruction is not limited to the US military base; the whole city would be destroyed.