A top South Korean military official on Friday said he assesses that North Korea has made substantial headway in acquiring the ability to make nuclear warheads small enough to mount on missiles, the Yonhap News Agency reported.
"Considering the nuclear development so far, I believe [North Korea] has made considerable progress in warhead miniaturization," said South Korean Adm. Choi Yun-hee at his parliamentary confirmation hearing to become the chairman of the military's Joint Chiefs of Staff.
The exact status of North Korea's efforts to miniaturize nuclear weapons is a major area of interest for the United States and South Korea. Pyongyang routinely promises to carry out nuclear attacks but these threats are not given much weight. If and when the Kim Jong Un regime is definitively understood to possess the ability to mount nuclear weapons on ballistic missiles, that will change.
Other key obstacles the North must overcome before it can be said to represent a credible intercontinental-ballistic missile threat to the United States include developing a reentry vehicle that can survive the passage back through the Earth's atmosphere and demonstrating a reliable ICBM launch capability. South Korea and Japan already are threatened by North Korea's short- and medium-range missiles.
In order to better defend itself against North Korea, Choi said the South should continue developing its national Korea Air and Missile Defense framework by enhancing its missile detection and interception abilities.
"If there is a possibility of the North using [nuclear weapons] and imminent danger, we have to launch a preemptive strike using the kill chain," the admiral said. "If there's still a nuclear threat, we have to counter it using the KAMD."
The kill chain refers to Seoul's plan to use ballistic missiles and fighter planes to destroy North Korean missile-firing sites before they can carry out launches that appear imminent.
North Korea on Friday lashed out at Seoul, Tokyo and Washington for conducting three-way maritime exercises, Agence France-Presse reported.
"The war drills show that the U.S.-Japan-South Korea tripartite military alliance has developed into the nuclear war alliance and has become operational in actuality," the North Korean Committee for the Peaceful Reunification of Korea claimed in a statement.