Why can't we get along with North Korea?

The more I think about the North Korean situation, the dumber it seems. It reminds me of the movie, The Mouse that Roared. North Korea is a non-entity. It is impoverished and largely isolated from the rest of the world.

The sanctions we imposed are obviously not doing any good. Why can’t we work out a deal by which we lift sanctions in exchange for them promising not to bomb us? We fought a long losing war with Vietnam. Now we get along with the Vietnamese just fine. Why can’t it be that way with North Korea?