No you can't, explain how they could know beforehand they were going to invade Poland.

The North Korea may come across insane, but Kim Jong-Il really isn't dumb. Considering the circumstances, he's not doing a bad job still having his country alive in 21th century. If he was an idiot North Korea would've collapsed a long time ago already.

North Korea has an infinatly stronger and bigger army than North Vietnam had, they're going to dig themselve in and if the USA tries anything the amount of casualities are going to be way higher than they can explain at home. An actual invasion is completely out of the question.