Will Brown do to Blair what Macmillan did to Eden at Suez?

The greatest part of the Blair premiership has been notable for its sideways, crablike movements. Even on the occasions when the Prime Minister has been clear in his own mind about his destination, he has been opaque with the public at large and even with colleagues. There is an embedded belief in No. 10 that openness about motives or objectives is the same as giving away battle plans to the enemy. This is the main reason why Tony Blair has often dismayed his friends by failing to show leadership – think of taxation, parliamentary reform, fox-hunting and, above all, the euro. He has never moved an inch forward unless there is a ready-made coalition and well-prepared lines of retreat.

That is why the Prime Minister’s 90-minute press conference at Sedgefield on Tuesday afternoon was so shocking. Blair endorsed a bold and vigorous course of action, namely the invasion of Iraq, in the face of the opposition of fully 70 per cent of the British people. Not merely that: a good half of his own party are against; international opinion is virtually unanimous in opposition; and Cabinet resignations can be taken for granted if Blair sanctions an invasion. Cherie Booth – never a force to be overlooked entirely – is said to harbour strong doubts.

It is true that Tony Blair enjoys the wholehearted backing of Iain Duncan Smith and the bulk of – though by no means all – Conservative MPs. But this source of support is unlikely to make the Prime Minister sleep better at nights, though it is not hard to imagine circumstances where it might conserve his parliamentary majority. Bush, Blair, Rumsfeld, Cheney and Duncan Smith stand alone.