When the intellectual history of the lead-up to the Iraq war is written, I suspect it will have to disentangle at least four different causal chains to understand why so many public commentators supported it (or, if they failed to support it, expressed their disagreement sotto voce ). First – the use of the Iraq war and the spread of democracy by force by a particularly unscrupulous crowd of conservative public intellectuals to, as they hoped, establish Republican hegemony. This was never a secret – read Kristol and Kagan’s 1996 Towards a Neo-Reaganite Foreign Policy for the blueprint – an argument in which the good of the oppressed of the world and the good of the USA inevitably redound to the dominance of the Republican party.
I'm afraid I don't see how thinking that what's good for the United States of America is also good for your political party counts as being intellectually "unscrupulous." And if it does, then Bill Kristol and Robert Kagan hardly have a monopoly on the vice. Practically every pundit and public intellectual thinks that their pet idea - whether it's neo-Reaganism, Sam's Club Conservatism, or whatever the heck Peter Beinart was selling his fellow liberals - is at once the solution to America's ills and the ticket to a lasting political majority. This can produce some deep silliness, like Linda Hirschman's argument that the repudiation of John Rawls will cement a new Democratic majority, but there's nothing particularly sinister about it.
In the case of Kagan and Kristol, one might add that nothing either one has written since things turned sour in Iraq suggests that they value GOP dominance more than their ideas about how the U.S. should act in the world. It's very clear that for both of them, the neo-Reaganism comes first, and the fate of George W. Bush and the Republican Party comes second.