Michael Kinsley: “The Freudian/Oedipal theorizing about finishing the job his father left undone is entertaining but silly. So is "Wag the Dog" speculation that Bush is staging a war for political reasons: The political risk of a bloody disaster surely outweighs any short-term patriotic boost. The lack of any obvious ulterior motive, in fact, is the strongest argument for taking Bush at his word.”
Kinsley dismisses almost outright two favourite arguments used by the left: that he's finishing the job for daddy; and that deflection away from scandals (in this case, scandals about companies, with tangential involvement of the government) back home are the motive for a strike against Iraq. The last paragraph of the article is the highlight.
It's funny how both Kinsley and Joe Klein note that Gore won the popular vote of the last election, which is entirely irrelevant. And I find it odd that people, like Weisberg (who tries to make the case against the case against war), are saying that "[t]he White House is proposing a radical new military and diplomatic doctrine for the United States—the right to intervene, unilaterally and pre-emptively, whenever we see fit." It's only really the first time they've said so publicly, and it's refreshing (although slightly dishonest in suggesting it's a new thing) in that they are acknowledging what has been policy for at least the last 50 years.
I haven't yet seen someone argue for invading Iraq in terms of 'opportunity cost', one of the few things I remember from Economics class in university. Opportunity costs are the costs of not doing something other than what you're currently doing (or about to do). (As an aside, some economists will tell you that efficiently-running businesses actually run at zero profit, if opportunity costs are taken into account.) Invading Iraq is favourable only if the costs of doing so outweight the costs of not doing so. So far conservatives firmly believe striking Iraq will save much in the future (e.g. keep Israel intact; get rid of someone not openly hostile against the United States but with some muscle to back it up), while those on the Left will argue many things: that the United States is being unilateralist (and nation-states are wont to do); that, as Klein argues, the outcome is less than certain, because of the complexities involved.
The best arguments against a war, which take into account President Bush's political interests (do you think he really listens to people who don't want to further his political interests?), are that in the political realm, it gains Bush nothing domestically, and something Photodude touched on earlier. The first President Bush lost to then-Governor Clinton because he failed to spend his political capital. The second Bush gained a huge amount of political capital from September 11th, and has so far failed to do Something Big with it. He risks doing the same with Iraq.