I've only just caught up with the fascinating exchange of letters in Slate between the British historian Niall Ferguson and the American political thinker Robert Kagan. This exchange raises what is to me the the key issue behind the current parlous international situation -- the chronic misunderstanding, or misrepresentation, of America's role in the world and its motives for waging war on Saddam Hussein.

Ferguson, who characterises himself as a passionately pro-US European, is nevertheless deeply offended by what he sees as America's unilateralism:

'What of America's alliances? Nobody can pretend this administration has treated them with the respect they deserve. The central failing of American foreign policy last year was the hubris of the Defense Department, epitomized by Secretary Rumsfeld's claim that the United States could invade and occupy Iraq single-handed, if necessary without British help—a gratuitous remark that could scarcely have been better calculated to undermine the already weak position of America's most loyal ally. Allies matter not just because they can provide effective military assistance. They matter because they help to confer legitimacy. And legitimacy is in many ways the crux of the matter.'

Ferguson draws brutal conclusions. The rest of the world now sees the US as 'not just an empire but now an evil empire' which is declining and will fall, and against which coalitions will now arise.

Kagan agrees with much of this, but points out that Europe is no better in coming up with a structure that provides legitimacy. Where he strongly takes issue with Ferguson -- quite rightly -- is over Ferguson's blithe assertion that the claim that Iraq possessed weapons of mass destruction was exposed 'not just as an intelligence failure but as a willful misrepresentation'. Kagan puts this ludicrous, if widely believed, canard through the shredder:

'I do strongly disagree with your characterization of this administration's "willful misrepresentation" of the Iraq WMD threat. The Bush administration made no more of that threat than the Clinton administration did. Everyone, and I mean everyone, believed Saddam had the weapons. And they were right. Iraq admitted to having stockpiles of chemical and biological weapons in the 1990s, and we were not able then, and we have not been able now, to discover what happened to those stockpiles. We have discovered ongoing weapons programs and, as David Kay reported, efforts to deceive Hans Blix and his inspectors about those programs right up until the eve of war last year. Count me as among the last holdouts on this issue. I honestly do not believe we yet know the final story regarding Saddam's weapons. But, in any case, the Bush administration did not engage in "willful misrepresentation," although the fact that it is perceived to have done so has certainly not aided the quest for legitimacy.'

I think this exchange still fails to answer the big question: why is the US, which (apart from Israel) is the principal victim of war by terror and has chosen to fight it in defence of everything the free world believes in, treated as an 'evil empire' because it has done so? And why is it blamed for 'unilateralism' when Europe on the one hand and the UN on the other made it crystal clear that they were not prepared so to fight? What in the circumstances was the US supposed to do -- sit on its hands and wait for the crop sprayers in jihadi colours to deliver clouds of nerve gas to Washington or Manhattan? Is multilateral suicide really preferable to unilateral defence?

Sure, the Americans' bombast and arrogance have meant they have made mistakes in Iraq which have brought the defence of the free world to the edge of disaster -- and we may yet topple right over. But without the US, there would have been no defence. And it is a dangerous blindness to brush that vital fact aside.