

Generally frowned upon to invade countries.
Ludicrously costly. Your tax payers will want to know why it’s more important than everything else you do with their money.
Immense suffering. Mostly by the people you’re trying to liberate but also your own troops and their families.
They have nukes and could probably blow up at least a few regional cities. If the regime is threatened they will most likely use them.
South Korea or China or Russia are the only countries with land borders. China and Russia find NK useful to have arround to annoy US. Seoul is within artillerty range of the border.
Building up a new state in it’s place is very difficult. Remember how the Taliban took back power about 15 minutes after the US left Afghanistan?
I was smarter.
That did not prevent me from being foolish like all kids are.