By John Rentoul

Independent on Sunday – 7 May 2006

What matters is what works, as the Prime Minister once said. It does not have to be pretty. It does not have to make any sense. It just has to get him through another worst week. The reshuffle did that. Against a band of enemies on his own side who can unite behind nothing more substantial than the demand for "a timetable", a demonstration of calculated ruthlessness was enough. The idea that the main thing wrong with Tony Blair's Government is his failure to name the day of his departure is silly. Imagine, for a moment, Blair granting his critics their wish.

"I hereby announce the timetable for the stable and orderly handover,"

he could say.

"I intend to stand down as Prime Minister on 1 February 2009. I shall stand down as leader of the Labour Party two months earlier to allow the party to organise a leadership election. I shall not be endorsing any of the candidates, and I shall make no further comment. Thank you."

What Brown's supporters mean is "go now", but it sounds more measured if they talk about the need for "stability". It makes no sense, but politics is not a rational business. The reshuffle was not logical either. If it was designed to strengthen the Government, then it should have been done before the local elections, not after. Four days ago, Charles Clarke was the right person to deal with the foreign prisoners problem. Now he isn't. A year ago, Blair used his renewed mandate from the British people to choose his Cabinet. Now he admits, in effect, that those choices were wrong.

In fact, it was quite a good reshuffle. When his back is against the wall, Blair rises to the challenge. He knows that he has muffed reshuffles before. This one had to be got right. The only glitch was Geoff Hoon's belief that he was "Secretary of State for Europe" in the Cabinet while Downing Street announced that he was a mere "minister" with the right to attend Cabinet meetings. But that was a deliberate punishment for trying to jump into the Brown camp too early.

And those are details. By the middle of next week, only one thing will be remembered about the reshuffle, and that is that Blair sacked Clarke. That advertises a simple and vivid message: that the Prime Minister is tough on foreign criminals and means business. The rest will fade quickly. The local elections were bad for Labour, but they were not meltdown.

Labour's share of the vote was about the same as in the local elections two years ago, just before a historic third general election victory. The timing of the reshuffle was a cynical – and mainly successful – attempt to distract attention from election results that turned out not to be as bad as Blair feared. He did not sack Clarke before the elections because that would have produced the wrong narrative. That would have been: local election drubbing despite Clarke's departure. I can understand that Clarke feels raw at being kept on as a scapegoat for ritual sacrifice. But it was illogical of him to say that he "disagreed" with Blair's decision to sack him when he offered his resignation only 10 days earlier. As it is, therefore, the big story of the reshuffle is: Blair callously disposes of friend and ally for failure to deliver.

It should achieve its purpose, which is to dam the flow of bad news stories about foreigners committing terrible crimes instead of being deported. Those stories had moved on from the former Home Secretary's original blunder, by which 288 foreign prisoners were released without being considered for deportation between August last year and March. Last week the media moved on to reporting quite different cases, of bad men who had been considered for deportation and who had not been deported. Clarke's failure to make the deportation system work drew attention to the fact that, even when the system worked as it was supposed to, most people are uneasy about the results.

The moment we should have known that the Home Secretary was doomed was not when Blair left the Commons chamber as Clarke rose to report on the hunt for the overlooked foreign criminals. That was bad, but not conclusive. The point at which it should have been possible to bet the mortgage on Clarke's removal came when he replied to Julian Lewis, the forensic Tory MP. Lewis asked about foreigners convicted of a serious criminal offence:

www.julianlewis.net/house_detail.php?id=780"How was it possible for the Prime Minister to say that these people would automatically be deported under the new rules, when he – the Home Secretary – has made it perfectly clear that they could not be?"

Clarke replied, gloomily:

"I have already dealt with the substance of the question."

Oh, no he had not. He does not usually avoid a direct challenge. The gulf between Prime Minister and Home Secretary yawned wide and unbridgeable, and Clarke did not even try to bridge it.

Only minutes before, Blair had had one of his taxi-driver moments.

"For years, we have not been deporting all those people convicted of a serious criminal offence. I say now, 'Let us deport all those people'."

Clarke, by contrast, talked mildly of a "presumption" in favour of deportation and promised to consult on whether a new law was needed.

In strict legal terms, the Prime Minister was, of course, talking nonsense. It would not be possible to deport foreign criminals "automatically" without revoking international conventions. No one can be deported to countries where they face persecution, torture or death, regardless of what crimes they have committed here. But Blair, sensing the deep damage inflicted on the Government's reputation by the foreign prisoners fiasco, was engaged in politics, not law.

His was the rhetorical style deployed by Margaret Thatcher: that of "the Government ought to do something about it". It was enough to outfox David Cameron. The Conservative leader came to his weekly clash with the Prime Minister armed with questions about whether Blair's asylum policy had shifted problems elsewhere in the system. He was unprepared for Blair's saying, in effect: "It's far worse than that. The whole system is rubbish and it has got to be changed completely."

It was enough, too, to seal Clarke's fate. Blair cannot change the law to deport "automatically" all foreign criminals the moment they have served their sentences. But he can change the Home Secretary so that it gives the appearance of decisive action. What matters is not what works on the ground, but what works in moving the media on to the next big story.

Sacking Clarke before the elections would have told the wrong story.