I'm not certain that I would blame Bush or his policies for the problems with North Korea. Maybe moreso Clinton, for giving them stuff (although I am under the impression that the Bush administration may have given them some aid as well), but in neither case do I think that there was an obvious way to stop North Korea if someone had just had the guts. Any military attack would likely have caused them to unleash their artillery on Seoul.
Maybe some people think that sacrificing Seoul would be worth it, but it is not plain to me that it would indicate a lack of nerve to take the position that we do not want to risk Seoul by attacking the North Koreans.
And short of military action, there is not much that we can do that would actually affect anything, at least not without China's (and maybe Russia's) help.
If we believe Mark Steyn, I suppose we could threaten to nuke Beijing and Moscow in order to force them into helping us, but - Hell, if I have to tell you why this is a stupid idea, then you're already lost.
That is all.