First of all, it's well-known that Bush didn't give a shit about "WMDs" in Iraq, he straight-up lied to the American public and he had his cabinet lie as well, to have a government where the leaders can look you straight in the eye and lie about something as huge as to bring about a war where your children will die is not a government I think is just, or right, we can do so much better. Money, Oil and taking out a dude that his dad couldn't, you know, kind of a clean up that daddy bush couldn't finish is what I think some of his reasons were. Bush went to Iraq alone, too, because of money and he wanted the war run exactly as he (or his buddies, like Daddy, Cheney and Rumsfeld to name just a few) wanted.
We can't go to N. Korea because China's got their back. Look in your history books like 55 years ago to learn more... And "when China wakes up" is just a stunning comment to me. They aren't a country that finds big business in war, they are just a big business country. They woke the fuck up big time about 15 years ago when they changed their economic system to a capitalistic type, while keeping their government largely communist. China doesn't go to war to prove themselves, even though they got thousands of nukes and an army that could topple us in a large-scale war. The US is run as a Fear-State since 9/11 and its hard for most people to think worldy when the news is telling you all about terrorists everywhere and stereotypes run rampant. China has woken up, just as the US, the "sleeping giant" woke up after WWII, but China didn't have to get bombed to become a superpower.
Now this is solely personal opinion, but I don't think at all that Bush invaded Iraq to keep the US on top. I think he did it for personal gain and control. If he wasn't at war, what do you think the people would find out? The truth of his sheistyness, people wouldn't have a war to be concerned about, they would be concerned about his domestic actions. He needs the war to stay as president, eventhough he's handling it poorly.
And come on, North Korea will not be "The World Superpower." They can't compete economically with the US, or China, or most of Europe. Hell, they can't compete with California. They have very little resources, and I honestly don't see a day when they will control the world's economies the way the current superpowers do.