THAAD (Terminal High Altitude Area Defense Missile) is a defense system with radar that senses enemy missiles and shoots them down.
On Jul. 8, the government declared THAAD   will be deployed in Seongju. The location was decided by considering military effectiveness. It can shield cities like Pyeongtaek, Gyeryongdae and Busan which are all important military points.
However, the residents of Seongju highly resisted the deployment. On Jul. 13, more than 5,000 people joined a rally and on Jul. 20, about 2,000 residents went up to Seoul Station Plaza and had a peace demonstration. They expressed concerns about the negative effects on their own health and sales volume of oriental melon. Oriental melon is a specialty of Seongju, and residents are anxious about the impact of THAAD’s radar on its growth.
Domestic opinions were divided among many interpretations. Regarding THAAD’s effect on the economic relationship with China, Foreign Direct Investment Professor Kim Young Han (Sung Kyun Kwan Univ.)   claims that “the withdrawal of THAAD in order to expand our economic cooperation is just a fragmentary understanding.” He argues that the contraction of economic cooperation between China and Korea has originated from the fact that Korea is no longer at a superior position in industry to aid the Chinese market  .
Additionally, Prof. Kim disagrees about the US army withdrawal from South Korea as THAAD disposition failed. Even though the US has a sizable number of armies in Korea, Japan, and the Philippines, they could not show any military edge in territorial disputes in South China Sea (West Philippine Sea). Thus, he thinks the US army will not withdraw for THAAD related reasons.
Prof. Koh Yu Hwan of North Korean Studies at Dongguk University, suggests another view. He claims, “Our way to make a living is to avoid one-sided subordinate relationships, and to increase interdependence with various countries,” and lists two big viewpoints on the issue. Firstly, the safety of Korean citizens precedes foreign resistance. Secondly, the aggravation of Korea’s relation with China and Russia will lead to economic depression in Korea.
Prof. Koh also expresses his opinion about the rumors going on about North Korea’s demise that North Korea will collapse internally, so nuclear weapon problem will be naturally solved. He refutes this with several reasons. Firstly, the charismatic  politics can continue under the state of crisis initiated by external forces like South Korea’s propaganda broadcast.
Looking from different perspective, there is a callout for self-defense of South Korea through stronger bonds with the US. Professor Hong Kwan Hee, assistant professor of North Korean Studies at Korea University, claims, “Since the modern form of international relationships is based on interdependence, the only key to successful alliance is putting aside self-reliant defense.” He said nations like China, Russia, and Japan cannot disdain Korea anymore when Korea has a strong alliance with US, and also expressed “Advanced nation treats even 1% possibility of danger.”
About domestic objection, Prof. Hong said “Requiring ‘acceptance of opinion’ in national defense problem has excessive characteristic. THAAD disposition location is decided purely by military security aspect, not pros and cons of residents. Residents can oppose, following their interests, but they have to  understand that is necessary for national security.”