Apparently, North Korea’s launch of a satellite “could lead” to … well, pretty much anything. And yes, it “could”. Why on earth it would is, on the other hand, the question that we must not ask.
It is no more permitted to wonder why North Korea would want to bomb Alaska than it was to wonder why Iraq would have wanted to bomb wherever it was that Saddam Hussein was supposed to have wanted to bomb, presumably (though entirely inexplicably) the British bases on Cyprus.
Still, if North Korea (or, indeed, Iran) really does want nuclear weapons, then she doubtless wants the ones that Iraq had. Capable of deployment within 45 minutes. Capable of reaching New York from Mesopotamia, so imagine how deep into the American heartland they could reach from Korea.
And completely undetectable by any means whatever.