On 6 March 2017, two THAAD launcher trucks arrived by air transport at Osan Air Base South Korea, for a deployment. Earlier that day, North Korea had launched 4 missiles. A Reuters article stated that with the THAAD defense system, a North Korean missile barrage would still pose a threat to South Korea, while an article in the International Journal of Space Politics & Policy said that South Korean forces already possess Patriot systems for point defense and Aegis destroyers capable of stopping ballistic missiles that may come from the north, in a three-layer antimissile defense for South Korea. On 16 March 2017, a THAAD radar arrived in South Korea. The THAAD system is kept at Osan Air Base until the site where the system is due to be deployed is prepared, with an expected ready date of June 2017. Osan Air Base has blast-hardened command posts with 3 levels of blast doors.