Paul - North Korea developed nuclear weapons because it is a communist dictatorship.
Communist dictatorships have the nasty habit of utterly destroying their economies, and when you're done raping your own country, you naturally turn outwards. North Korea developed nuclear weapons not because it's afraid the US might attack them (why on earth would it?), but because it needs a bargaining chip to continue it's ludicrous demand for fuel, food, and money, none of which goes to the starving citizens. What is your solution? Feed the NK army, fuel their tanks, and finance Kim Jong Il's masturbatory excesses? And when Kim Jong Il wants more, what do you think he'll do?
Calor - there is no comparison between Pax Britannica and Pax Americana. Pax Americana doesn't require active occupation or domination of countries, it just requires the threat of overwhelming military force. It does not suffer from the pitfalls of empire-building because it is not an empire, but a sword of Damocles hanging over the world, keeping it AT PEACE.
If you take away the advantage the US military superiority gives, Pax Americana disappears. What do you want instead? Bellum Multilateratum?
Don't belittle Iraq - it's about as big a fish you can fry without going nuclear, and no one is going nuclear. Unless the Bush Doctrine gets nixed, the US retreats, and everyone sits back and waits for some nutjob group of moonbarkers (insert Islamist/communist group/theocracy/dictatorship name here) to get their hands on a nuke, which they will then detonate in some metropolitan area somewhere, killing tens of millions.
Pax Americana exists because America is strong, and feared by those who would otherwise trounce around like Genghis Khan, Hitler, Stalin, Hirohito or a host of others, leaving a wake of destruction all too familiar from history. America is strong not because it goes around killing everyone in sight, but because it has the *capability* to do so. Not one person in their right mind living in a modern liberal democratic state is afraid that the horrible Americans will come attack them. It's a ridiculous notion. So it is a cultural hegemony, an attack on diversity, a chauvinist ethnocentric invasion instead. I'm sorry, but this is one non-American who has absolutely no issues with a cultural, anti-diversity, ethnocentric invasion against diseased parts of cultures. No one told the Japanese to abandon eating sushi or Sumo wrestling. They did, however, tell them to root out the militaristic, ultra-nationalist facet of their culture. This is not a bad thing. Look how nice the Swedes are, now that they don't go around in horned helmets, robbing half of Europe. The world, however, is less diverse, mostly because there are less cultures who practice rape, looting, and pillaging on a regular basis. For shame.
The Bush doctrine requires the same of the Middle Eastern cleptocracies, theocracies, and hatemongers - sit down and shut up, stop killing people, or we'll beat your ass. And nothing else will work.
