What is THAAD?
The Terminal High Altitude Area Defence (THAAD) missile system is designed to counter and shoot medium and intermediate range ballistic missiles.
THAAD’s powerful radar allows for missiles to be detected and destroyed before they are launched. With a range of up to 200 kilometres and the ability to reach altitudes of 150 kilometres, it is specifically designed to counter a possible missile attack from North Korea.
Lockheed Martin, the security and aerospace company that was the main contractor for the system said it is highly mobile and is comprised of interceptors, launchers, a radar, a fire control unit, and support equipment.
THAAD in South Korea became operational on Tuesday.
Why is THAAD controversial in South Korea?
“Just suddenly one day, Seongju has become the front line, wars today aren't just fought with guns. Missiles will be flying and where would they aim first? Right here, where the THAAD radar is, said Park Soo-gyu, a 54-year-old strawberry farmer.
Farmers like Park who live in the tiny village are also concerned about the effects that THAAD's electromagnetic waves will have on them and their crops.
Protesters have also congregated in the sleepy village. Banners saying: "Withdraw the illegal THAAD immediately" and "Stop US militarism" hang from trees and fences.
As South Koreans head to the polls to vote for a new president next week, THAAD has become a divisive issue. The front runner Moon Jae-in said the new government should have the final say on whether the missile detection system stays or goes.
Is there a real need for THAAD?
Seoul and Washington think that the likelihood that North Korea could fire nuclear weapons is real and they should be prepared.
Since Kim Jong-un took over as the supreme leader in 2012, North Korea has often displayed its nuclear capabilities to the world. For South Korea, this has meant sleepless nights.
By operating THAAD, South Korea said it would be able to protect about half or about two-thirds of their citizens from North Korean nuclear and missile threats.
Pyongyang has repeatedly flouted United Nations resolutions and last year alone it carried out two nuclear tests and over 20 missile tests.
After missile tests last month, the US warned that the “era of strategic patience is over” and THAAD’s completion was accelerated. Washington said THAAD would protect its troops in Asia and offer its allies South Korea and Japan more safety.
“Any attack on the United States, or our allies, will be defeated, and any use of nuclear weapons would be met with a response that would be effective and overwhelming,” US Defense Secretary Jim Mattis said in January.
How do South Korea’s neighbours feel?
China and North Korea are allies but Beijing is also becoming fed up with Pyongyang’s continuous testing.
However, China and Russia, two of North Korea’s allies feel that the deployment of THAAD would destabilise security in the region.
Beijing is worried that THAAD's advanced radar system will allow the US to track the movement of Chinese military hardware on the ground. “THAAD’s X-band radar can peer into Chinese and Russian territories, breaking security balance and fuelling arms race in the region,” Chinese state media reported.
Moscow feels the same way and said it has been set-up to monitor neighbours
Russia’s Deputy Foreign Minister Gennady Gatilov, in April, said that the anti-missile system posed a threat to "the existing military balance in the region."
— Russia in USA 🇷🇺 (@RusEmbUSA) April 28, 2017