KCNA/Reuters
North Korean leader Kim Jong Un (C) guides the multiple-rocket launching drill of women's sub-units under KPA Unit 851, in this undated photo released by North Korea's Korean Central News Agency (KCNA)
Adm. Bill Gortney told reporters at a Pentagon news conference on April 7 that Pyongyang had the capability to place miniaturized nuclear warheads on its latest KN-08 intercontinental ballistic missile (ICBM).
Pyongyang has "the ability to put a nuclear weapon on a KN-08 and shoot it at the homeland," Gortney said.
But South Korean Vice Defense Minister Baek Seung-joo countered at an April 13th press conference that Gortney's remarks were "not made with a thorough assessment of North Korea's capabilities."
According to the Wall Street Journal, Seoul's official position is that while North Korea has made strides towards miniaturization, the north has so far failed to produce a nuclear warhead small enough to be mounted on a missile. South Korea has also raised the question of whether the KN-08 is actually functional, given that North Korea has yet to flight-test the missile.
Still, Gortney did say on April 7 that the US opts for a more cautious assessment of North Korea's capabilities and is "prudent" in its deicion-making when it comes nuclear weapons. So US policy may be thinking in terms of nuclear miniaturization and a possible ICBM capability as a precaution, even if there's no "smoking gun" to prove that North Korea currently has either technology.
This position was repeated by Lt. Col. Jeff Pool, a Pentagon spokesman, who told the WSJ that "given the consequences of getting it wrong, it is prudent for a military planner to plan for the worst."
North Korea experts John Schilling and Henry Kan estimate that the KN-08 would have a maximum range of 5,600 miles, making the missile capable of hitting the West Coast of the continental US. The weapon, however, is unlikely to have the accuracy required for precision targeting of large US cities.