The US Army’s Terminal High-Altitude Area Defence (THAAD) system that has been deployed in South Korea is the most advanced interceptor in the world and is designed to shoot down ballistic missiles in the terminal phase of their approach to a target.
The need for the system was identified as far back as the mid-1980s but gained new momentum in 1991 when Iraqi forces launched attacks against coalition targets with Russian-built Scud missiles during the Gulf War.
Developed primarily by Lockheed Martin, with input from a number of other companies, including BAE Systems, a THAAD interceptor carries no warhead but relies on advanced infra-red tracking to intercept its target and the kinetic energy of the impact to destroy the inbound missile.
A kinetic energy strike minimises the risk of detonating a conventional warhead, while it will also not trigger an explosion of a nuclear warhead.
Each missile weighs just over 1,980lbs and is 20 feet long. The system has an operational range of around 125 miles and a missile travels at Mach 8.24 – or slightly more than 6,260mph – to its target.
THAAD missile defence system
A single battery is made up six launchers that are mounted on a truck, 48 missiles, an AN/TPY-2 radar unit and associated command and communications facilities.
The US initially planned to deploy THAAD in 2012, but development was sufficiently rapid that the first battery was delivered to the US Army, at Fort Bliss in Texas, in 2008.
THAAD batteries have been deployed in the United Arab Emirates, Turkey and, most recently, South Korea.
Seoul initially approached the Pentagon about the capabilities and cost of THAAD in October 2013, but later decided to develop its own long-range, surface-to-air missile.
The crisis on the Korean Peninsula has deepened far more rapidly than Seoul anticipated, however, and the US and South Korean defence ministries agreed in July 2016 that THAAD would need to be deployed by the end of the following year.
That decision triggered concern and protests at home and abroad.
People living near the planned site of the new unit, a golf course in North Gyeongsang Province purchased by the South Korean government specifically for the battery, have protested that the unit’s radar is harmful to their health.
They have also complained that siting THAAD close to their towns, about 180 miles southeast of Seoul, makes them a target for a North Korean first strike.
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