First, I think America/South Korea would win decisively. True, Pyongyang is the most heavily defended city in the world, but it is defended with out-dated equipment. Antiaircraft flak is great when you are shooting down B-24s over Germany. It’s not so impressive against missiles coming in from outer space. To win a war you need a good economy, something North Korea does not have (true, America doesn’t have a good economy either, but we have enough of an economy to fight one more war–though this war would probably bring it tumbling down).
Fighting an air-war against North Korea, I think America will do well. America/NATO’s “shock-and-awe” style of fighting is impressive. The problem is actually taking North Korea. Fighting tank-warfare on flat terrain like Iraq and Western Europe is one thing. Mountain fighting is quite another (and this is one reason I think the US did NOT initially send ground troops into Serbia in 1999. Serbian special forces holed up in the mountains would have easily brought down yet another empire).
Secondly, while I normally despise neo-conservative/neo-liberal adventurism, I probably would support this war. North Korea truly does enslave and terrorize its people. It would be sad to see a free, market economy of South Korea reduced to slavery.
Thirdly, even if I think a war with North Korea is morally legitimate, I do not think it is a good thing. There could be massive loss of military and civilian life on both sides (both armies have roughly one million men, corralled into a very small land mass). Wars are expensive (the Iraq war costs the average family in Texas $46,000 per year) and really hurt economies. Even when we win this war–as I think is beyond doubt–this will be another nail in the coffin of the American Empire. Like the British said after they won Bunker Hill, “Let’s hope we don’t have too many more victories like this.”
While neo-conservatives/neo-liberals have never been too concerned about morally justifying their actions, I think a better case can be made for war with N.Korea than with Iran. Ahmaninjad, for all his problems, is a lot saner than some of the leadership in Washington D.C., and light years morally superior to the leadership in Tel Aviv. North Korea, as mentioned above, actually does pose a legitimate threat to much of Asia.
One other thing to keep in mind: a lesson we failed miserably in learning from the post-Cold War is there are worse things in the world than Communism. The mythos of the West (mythos means story of salvation) is the inevitable march of democratic capitalism throughout the world (funny how this sounds very similar to the inevitable march of the global proletariat). Therefore, in removing a communist country, so the reasoning goes, we are making the world purer and safer.
Ah, but as Samuel Huntingdon points out, the 1990s were far more horrific for world peace than the Cold War. It’s great that Communist regimes fail. But there are other evils in the world. Not to mention America is 0 for 10 in successful regime changes and nation-building. That doesn’t mean we shouldn’t defend against a legitimate threat. It’s simply putting realist glasses on unbridled patriotism.
Anatoly Karlin at Sublime Oblivion gives a very fascinating scenario of how the next Korean War will be fought.