After so long in full flow, Michael Ignatieff is finally brought to a halt. Not a shuddering halt, just a pause, temporary and short, but a definitive pause.
Effortlessly articulate, for an hour in conversation he has been all the Ignatieffs you can remember. The highbrow 1980s chat-show host, arch and clever; the TV journalist offering horrifying reportage; the smart academic. Most of all, in his latest incarnation, he has become the defender of a fight against terrorism in the name of democracy.
So, the question arises, does he hate those people who seek to justify the damage to politics in Israel and the West Bank caused by suicide bombers?
He stops at last. But it’s only a second or two before Ignatieff gives a hollow laugh.
"I think hate is an appropriate word," he says slowly. "There are a lot people who believe the right way to think about politics is to take the hate out. But sometimes hatred concentrates the mind.
"To say you hate them is not to say they’re monsters. But their politics is the death of politics; the violence they use confiscates all other possibilities in Palestinian society. You can’t object to it because you might die; if you support them you just risk creating another martyr. It’s a total nightmare. It will take enormous courage for the Palestinians to get up and say ‘This is not the way’. But until they do, Hamas is leading them right over a cliff."
Even in a comfortable Edinburgh restaurant, Ignatieff is that awesome thing, the militant liberal. If it’s a beast which can be derided on the British left, in America, the same animal offers a principled and high-profile critique of President Bush’s foreign policy.
It’s perhaps no surprise then that he recently returned to the US to teach human rights at Harvard, where he gained his doctorate, and to write for the New York Times. Nor, indeed, given his impressive credentials, that he should have been invited to follow Albert Schweitzer, Niels Bohr and Iris Murdoch and present the Gifford Lectures at Edinburgh University.
He is soon to give the fourth of six lectures on political ethics in an age of terror, in which he seeks to delineate the lesser evils which democracies must countenance in the fight against the greater evil of nihilist fundamentalism.
These are dark waters. Yet the protest movements which helped form Ignatieff’s beliefs a generation ago still, he claims, leave him an optimist.
His was born in Toronto, and was a student in the city, just as its university became a centre for young Americans resisting the Vietnam draft. Arguments ran long into the night among opponents of the war, between those, like Ignatieff who regarded it as a betrayal of the principles of the American republic and others further left who regarded Vietnam as an imperialist campaign in defence of monopoly capitalism.
These days, his hair grayer and his face wan, that experience still lingers. At 55, he is routinely cited as one of the most influential figures on the American left to have supported the "War against Terrorism", but he draws a sharp distinction between himself and one of his supposed bedfellows, the journalist Christopher Hitchens.
Fted by the right for his bellicose polemic, Hitchens is the former International Socialist, who now dreams of drinking champagne in Baghdad. No such chutzpah from Ignatieff. He snorts: "‘Hitch’, what can you say? I love champagne, but there will be nothing to celebrate and no-one to celebrate with. I’ve met the Iraqi opposition, they’re not the greatest bunch of guys."
Later, oiled by the meal we’ve enjoyed, the difference is still more distinct: "It’s always said, ‘Once a Trot, always a Trot’. I’ve slightly that feeling about Hitch. I’m glad he’s on the train, he’s discovered all the virtues of liberal democracy, but it’s a little late, to be blunt."
This is the principled liberal, the essence of whose philosophy lies not in what opinion he holds, but in how he holds it. Ignatieff is not dogmatic, but tentative, conscious that the human rights premises which underlie his support for American foreign policy could - quite reasonably - lead others to opposite conclusions.
Often his problem is simply having his case heard at all, because the war on terrorism, to the ordinary citizen, sounds like bad weather, far away. Even when he does engage in debate, he spends much of his time arguing against a kind of angelic moral perfectionism, from those who beg an adherence to a system of criminal justice which terrorists simply will not respect.
But as he chivvies along the bleeding hearts, so he holds back the hawks, the folks set on a turkey shoot. It’s plain to Ignatieff, "If we don’t pay some attention to constitutional liberty we’ll end up betraying the society we’re trying to defend."
The lines between good and bad, between lesser and greater evils, at times seem infinitesimally thin. In the first of his Gifford Lectures Ignatieff held up the dark world of torture to the light.
"Torture bothers me enormously," he says now, "because that’s a bridge I’m not prepared to cross under any circumstances. Let’s be clear what I mean - I mean attaching electrodes to your genitals, pulling out fingernails and stuff."
Torture, he says, corrupts the torturers and its use is difficult to control; anyway it does not provide reliable information. And he adds, terrorists have rights: "we owe duties to people who owe no duties to us". Torture, he concludes, can never be a lesser evil.
If this is enough to make a hawk snort, more dove-like critics suggest the language of human rights conceals an apologist for American colonialism. Ignatieff doesn’t care. "I don’t lie awake at night wondering whether the British left thinks I’m an apologist for anyone. There a lot of people who owe their freedom to the Americans: the Japanese, the Germans, the Bosnians, the Kosovans, the Afghanis - that’s five. By freedom, I don’t mean some absolute state of bliss, I just mean relief from tyranny."
Again, it may be unpopular but he believes the United States has become the sole guarantor of order in the world. Anything else is fantasy. He assumes shopkeeperly mode: "You don’t like the Americans? How about the Chinese or the Russians? Oh, you don’t like either of those either. How about the Europeans? They can’t agree fish quotas in the North Sea, for Chrissake.
"These are the cards we’ve been dealt."
But at this point in history, for Ignatieff the issue has become whether the Americans can continue to offer stability. And here - unlike Hitchens - he is ready to get off the bus to Iraq.
Make no mistake, he says, this is a grade ‘A’ odious regime. "But you can just make the case for intervention only if you put together two things - massive human rights violations internally and possession or perspective possession of WMD. Neither on their own is enough to justify coercive military force. To put the two together is like a binary weapon, it begins to justify intervention.
"Am I blind to the humanitarian consequences of war? No. But we are talking about lesser evils. It is a very unpleasant set of choices between bad options."
So he could accept intervention? It’s only a qualified yes, for his doubts over Washington’s policy persist, particularly in their apparent belief that they can free oppressed Iraqis but leave ordinary Palestinians to their fate.
"It’s not the military problem that’s difficult. The Americans are probably right to think they can knock this regime off quickly. But nobody is very good at nation building, and nobody knows how to get peace in the Middle East. Unless you put both of those together in the equation, it’s just making trouble.
"This is not a kind of religious issue, an issue of anti-Americanism. It is an assessment of an agonising problem in the public policy of major states. It’s not about the triumph of good over evil, it’s about whether you can use a lesser evil to avoid a greater."
He recalls a visit to Gaza in the 1980s, a place ravaged by conflict. All that time and no peace - two decades later, when alleged terrorist cells are found in Edinburgh or North London, the failure to win a settlement in the Middle East causes agonies all over the world.
"It took us far too long to realise these places are not on Mars. This stuff ends up, through a chain of consequences we don’t understand, to an Algerian cell by the Hibernian football ground. Or some bunch of weirdoes in Wood Green grinding out castor oil nuts."
Exasperation takes hold: "Jesus Christ," he snaps. "The liberal in me understands this - we have surely made a lot of mistakes."
The Gifford Lectures continue in the Playfair Library, Old College, Edinburgh, at 5:15pm, tonight, tomorrow and Thursday.