Yes, but the damage would already be done, and they could probably continue asymmetric attacks with smaller boats for a while. Even short-term economic pain isn't something the Bush Administration would be too willing to abide, since it'd interfere with their tax cut agenda.
We had to tilt the scale pretty heavily to keep them from winning, and that was a war on their frontiers (and also the Iraqi army was much, much stronger then than in 1991 or 2003), but an occupation of the country would be much harder.
The Iraqis fielded just shy of 400K in 2003. North Korea is more complicated since they haven't used their army in decades and their numbers are probably unreliable, but on paper they've got about 2 million active and reserves. And as much as on paper may be inflated, the whole society is designed for mass mobilization, so I could imagine them fielding even more troops than that if they could supply them, which they admittedly probably couldn't.
They'd be unlikely to shoot at us, but they'd for sure send troops in to stop the inevitable refugee crisis that would ensue once Pyongyang collapsed. And they'd have so many other ways than brute force to make the whole affair unpleasant for us that it's really not worth contemplating regime change in North Korea without them. The South Koreans know this and would also insist that we have their approval first, of course.
I'm really not sure. A partition plus oil sharing arrangements ideally, but it depends on who'd be likely to win elections that got instituted, and I don't know nearly enough about Sudanese politics to say. That in turn would depend on if there was a partition or not, or whether political parties would be delineated by ethnicity and pit Arabs against blacks, and this could get very complicated, of course.
More like its alliances with Iran and Russia, plus the effects that it falling into disorder would have on Turkey and Lebanon.
That's probably true, but it's enough to mean that nobody really sympathized with them. Most other governments, even most dictatorships, would still get some defenders as victims of American aggression if we up and attacked them.