North Korea responded with the threat of nuclear war Sunday to comments from air force professors that South Korea should consider a pre-emptive strike against Pyongyang. “The ‘pre-emptive attack on the North’ means provocation of a nuclear war,” a spokesman for Pyongyang’s Committee for the Peaceful Reunification of the Fatherland said in a statement carried by the official Korean Central News Agency. The comments came in response to remarks by South Korean air force academy professors, who told a seminar in Seoul earlier this month it was time for Seoul to consider a “pre-emptive attack” on North Korea as an option to incapacitate Pyongyang. The North’s spokesman repeated on Sunday Pyongyang’s nuclear deterrent was actually targeting what he called the US “nuclear threat”, not South Koreans.