The United States military has begun deploying the THAAD missile defense system in South Korea this week, a long-awaited move for the South Koreans that face an increasingly significant threat of North Korean missile attack.

The Terminal High Altitude Area Defense (THAAD) system is a defensive weapon platform designed specifically to shoot down short and medium range ballistic missiles.  According to Lockheed Martin, the primary contractor tasked with the project, each system is comprised of five primary components: the launcher, the interceptors, a radar system, a fire control unit, and support equipment.

The system works fairly simply: the advanced truck based radar first identifies a missile launch, and those manning the THAAD assess and identify the threat.  They then launch an “interceptor” at the missile.  The interceptor fires like a traditional missile, but is not equipped with an explosive warhead, instead it impacts the offensive missile and destroys it with kinetic energy.

Each THAAD battery includes at least six interceptor launchers that can carry up to eight of the kinetic energy missiles each.  The lack of explosive warheads on the interceptor missiles speaks to the platform’s distinctly defensive capabilities, but the Chinese have voiced a number of complaints about the presence of the THAAD systems not because of the potential for missile strikes, but rather because of the powerful radar system at the heart of the THAAD defensive strategy.  The Chinese believe the radar systems (AN/TPY-2 X-Band radar) on board each THAAD battery could be used to spy on Chinese airspace – and as a result, have voiced serious objections to its deployment in Japan or South Korea.

“We firmly oppose the deployment of THAAD,” said Geng Shuang, a spokesman for China’s Foreign Ministry on Tuesday. “We will resolutely take necessary measures to defend our security interests.”

“All the consequences from this will be borne by the U.S. and the ROK,” he added, referring to South Korea. “We strongly urge relevant parties to stop deploying it and not travel down the wrong path.”

The need for a THAAD missile defense system in South Korea has never been more palpable, however, as the North Koreans have tested medium range ballistic missiles a number of times in recent months.  Earlier this week, Kim Jong Un himself oversaw the launch of four missiles into the Sea of Japan, three of which landed within 250 miles of the Japanese shore, an area commonly accepted as Japan’s exclusive economic zone.  Some have suggested that these launches were intended to demonstrate (or to practice) North Korea’s ability to target and effectively destroy American military installations on the Japanese island – where more than 50,000 American service personnel are currently stationed.

“Continued provocative actions by North Korea, to include yesterday’s launch of multiple missiles, only confirm the prudence of our alliance decision last year to deploy THAAD to South Korea,” said Navy Admiral Harry Harris, commander of the U.S. Pacific Command. “We will resolutely honor our alliance commitments to South Korea and stand ready to defend ourselves, the American homeland, and our allies.”

It’s important to note that, had the four missiles launched into the Sea of Japan on Monday been aimed at American military outposts in South Korea, or at South Korea’s capital city of Seoul, the Aegis missile defense system utilized by the American Navy may not have been able to shoot the missiles down.  The THAAD system is designed to work alongside the existing Aegis system, sharing radar and tracking data to ensure friendly forces have the best chance at detonating a missile before it reaches its intended target using whichever platform is best suited for the situation.

“The deployment could be completed within one or two months, and it can be operational as early as April,” a South Korean military official told reporters in Seoul.  Although there has been some political backlash to the deployment of the system within South Korea, the government is intent on having the THAAD system operational as soon as possible.  For the time being, the components of the THAAD system that have arrived are being housed in the U.S. air base at Osan.

Images courtesy of Lockheed Martin/Raytheon