Jim Henley gets to the root of it:
What all of us had in common is probably a simple recognition: War is a big deal. It isn’t normal. It’s not something to take up casually. Any war you can describe as “a war of choice” is a crime. War feeds on and feeds the negative passions. It is to be shunned where possible and regretted when not. Various hawks occasionally protested that “of course” they didn’t enjoy war, but they were almost always lying. Anyone who saw invading foreign lands and ruling other countries by force as extraordinary was forearmed against the lies and delusions of the time.
Hence the necessity for fabricating the WMD stories back in ’03. Absent those convinced by those, the basic split was never left/right but between people who thought that war should be a casual instrument of policy and those that thought a predisposition against war should be a basic rule in international politics, or who thought that it actually was one.
You can see the consequences of the former mode of thinking in Jonathan Powell’s bizarre comments about al Qaeda last week. For people like Powell, 9/11 was above all a policy opportunity, something meant to enable the reshaping of the Middle East. What al Qaeda actually did in New York mattered much less. That opportunity has been taken, so as for al Qaeda…kill, negotiate, whatever.