According to Harold Macmillan, the hidden trap which destroys the careers of prime ministers was "events, dear boy – events". Few prime ministers have proved more adroit at dealing with events than Tony Blair. He always found the words to match the public mood.
War with Iraq is not an unforeseen event. Mr Blair has known for months that the US might launch a military strike. He always knew that getting the UN Security Council to sanction war would be a diplomatic challenge, and that sending in British troops would provoke vehement opposition at home. If the past week has seen an "event", in the Harold Macmillan sense, it was that the French Foreign Minister turned out to be cleverer than the British had thought.
And yet, with all this knowledge, Tony Blair has walked with eyes wide open into a crisis so serious that his political survival is at stake. Even yesterday, the Labour Party stewards who kept troublemakers out of Glasgow's conference hall for Mr Blair's speech could not prevent a logical contradiction from planting itself in the centre of his argument.
Mr Blair began with an assurance that "I hope even now that Iraq can be disarmed peacefully, with or without Saddam", and ended with the claim that "ridding the world of Saddam would be an act of humanity – it is leaving him there that is inhumane". But if it is "inhumane" to leave Saddam in power, why does Mr Blair "hope even now" to do just that?
A political strategist as experienced as Tony Blair ought to have been able to work his "line to take" before the crisis began, rather than find himself fishing around for one now. If the "line" is that Saddam Hussein has to be overthrown on humanitarian grounds, it raises the question as to why Hans Blix and 260 UN staff have been sent unprotected into a war zone.
However, Mr Blair can be given credit for being consistent about what he is going to do, even if the reason for doing it has changed. He has a long memory, and will recall vividly how Neil Kinnock was humiliated by Ronald Reagan in 1987. Mr Blair was never going to make room for Iain Duncan Smith to build the kind of rapport with George Bush which Mr Blair himself had with Bill Clinton. He calculated long ago that it was worth taking flak on the domestic front to protect his relationship with Washington.
Where Mr Blair appears to have miscalculated was that he was supremely confident that the UN Security Council would pass a second resolution, and that British public opinion would eventually come round to supporting war.
That confidence took a body blow on Friday afternoon, after Hans Blix has presented his updated report. The report itself contained roughly what the world had expected. What shocked the American and British delegations was the reaction in the room to a witty speech by the French Foreign Minister, Dominique de Villepin.
France had been traduced in the American and British press all week for embodying "Old Europe". One US congressman suggested on BBC's Today programme that the nation of Molière, Flaubert and Proust had no culture. M. de Villepin adroitly turned "old Europe" into a joke at America's expense, and the room erupted into spontaneous applause for his call to give the weapons inspectors more time.
UN staff were expecting the US and Britain to produce their draft of a second resolution within 24 hours of Mr Blix's report. None came, though British officials say there may be one this week. But the confidence that they can find a set of words with which France, Russia and China will agree has gone.
Before yesterday's marches, more than 100 Labour MPs and at least 70 MPs from other parties had indicated that they will oppose a war that is not UN sanctioned. That number is likely to grow after the demonstration which filled the streets of London. Tony Blair will also come under pressure to allow a vote in the Commons before he sends in British troops, leaving him in the ghastly position of having to lean on Iain Duncan Smith for parliamentary support. For the first time since 1997, experienced Labour politicians are beginning to wonder whether their Prime Minister will still be in office by the summer.
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