Experts are calling for South Korea to improve its missile defenses given the growing threat that North Korea will one day be able to make a nuclear warhead small enough to be carried by a rocket.
Prof. Choi Bong-wan of Hannam University said he carried out a computer simulation where North Korea fires a medium-range ballistic missile tipped with a nuclear warhead. The aim was to see what types of interceptor missiles would allow South Korea to deal most effectively with the threat.
Choi was speaking at a seminar hosted by the National Assembly's Defense Committee on Wednesday.
In one simulation, the North Korean Rodong missile with a range of 1,000 km carrying a 1-ton nuclear warhead reached Seoul within 11 minutes and 25 seconds, he said.
A Rodong missile with a shortened range of 300 km fired at a high angle toward Seoul would give a PAC-3 missile, a strong candidate for South Korea's missile defense, only one second to intercept at an altitude of 12-15 km.
A THAAD missile, which is another option for South Korea, would have a window of opportunity of 45 seconds to intercept an incoming missile at an altitude of 40-150 km.
And an SM-3 missile, another possible candidate, would have 288 seconds to intercept the potential nuclear missile at an altitude between 70 and 500 km, he added.
Currently, South Korea has only PAC-2 missiles, whose capability is much poorer than the PAC-3's, and is now seeking to purchase PAC-3 missiles. But Choi suggested that upgrade would offer little defense against a determined North Korean attack.