Sure. And I really could have picked any nuclear powers but I chose them as they are relatively small players.
In addition to iNow's very good description...
The point I was making was that the approach to any nuclear power is not based on what happened with them today but what has happened with them over a longer period of time. India and Pakistan could harm the United States with nuclear weapons, but the reason we are not dealing with them like we deal with NK is because they have not been threatening us or our allies in a prolonged fashion like NK has been. While we have had spats with Pakistan, and Pakistan with India on an ongoing basis, none of the three has a history of nearly continuous threats of annihilation of the other.
If someone shows you a bat and threatens to hit you with it every time you see them, you tend to act toward them like they might actually follow through one of those times.