Well as we saw from WW2 and how Britain had failed to do anything to prevent Hitler's rise I don't think it would be a good idea to sit back and do nothing. We let Hitler rearm and gain territory and sitting back and letting North Korea expand their nuclear capabilities is not a great thing.

That is kind of what I was thinking.

At least North Korea will probably not be able to make anything as advanced as the Russian missiles which can constantly change flight path to prevent it being taken down by an antiballistic missile so if NK were to launch anything a SAM should be able to deal with it.

Yes that may be possible.