By Kang Seung-woo



South Korea and the United States will for the first time carry out a joint exercise aimed at destroying nuclear and missile facilities in North Korea as early as March, defense officials here said Tuesday.



For the joint training, the allies will apply the "4D Operational Concept," which is to "detect, defend, disrupt and destroy" Pyongyang's missile inventory, including nuclear, chemical and biological warheads.



Last November, Defense Minister Han Min-koo and U.S. Defense Secretary Ash Carter approved the implementation guidance on the concept as part of efforts to strengthen tailored deterrence against North Korea's nuclear weapons and other weapons of mass destruction (WMDs).



"While developing the counter-missile operations based on the 4D concept, the South and the U.S. are seeking to apply it to a joint exercise for the first time," a government official said Tuesday.



Washington's strategic military assets, including B-52 bombers and the nuclear-powered aircraft career USS Ronald Reagan may participate in the exercise, sources said.



The Ministry of National Defense reported the training plan to the National Assembly National Defense Committee, Thursday ― a day after the North's fourth nuclear test.



"A joint exercise, aimed at enhancing countermeasure capabilities against the North's nuclear and missile threats, is necessary. In this respect, until recently, the two sides have conducted table-top exercises four times using the 4D concept," defense ministry spokesman Kim Min-seok said during a briefing.



Seoul and Washington are likely to implement the 4D concept in the upcoming ROK-U.S. joint exercise Key Resolve, scheduled for March. Key Resolve is a simulation-driven, combined command-post exercise.



A use of the intensified anti-missile program comes on the estimation that the Kim Jong-un regime's pursuit of nuclear weapons and long-range missiles has gone been beyond the "wait-and-see stage."



While it remains unconfirmed whether or not Pyongyang actually detonated a hydrogen bomb in its fourth nuclear test, the North is believed to have entered the early development stage of the H-bomb, which is many times more powerful than conventional plutonium or uranium based nuclear weapons, raising the need for the allies to demonstrate their unity and force.



In addition, given that diplomatic efforts have failed to stop the North from boosting its capabilities to miniaturize warheads, the South Korean and U.S. military are scrambling to put the 4D concept into action earlier than expected.



In the joint exercise, the allies are expected to update their target list of the North's nuclear facilities and missile bases because in an emergency situation, preemptive strikes against such targets could stop Pyongyang from using such weapons or delay its use of them.



Based on the 4D strategy, the allies can detect a North Korean missile launch in less than one minute, and identify a target and decide a weapon to counter it within one to three minutes, which would enable a strike against the missile shortly afterwards.



"The allies need to formulate a plan to counter North Korean missile threats at any time," said Park Hwee-rhak, dean of the Graduate School of Politics and Leadership at Kookmin University.



"A well-organized ROK-U.S. missile defense system needs to be formed to protect major cities such as Seoul."



