Steve Richards: He had one chance to take risks. But Brown has wasted it with this macho posturing

Ministerial energy is sapped and political capital is devoured over what is at best an irrelevant diversion. After endless, increasingly bizarre concessions, ministerial meetings with Labour MPs, media interviews and newspaper articles, Gordon Brown won the vote in the Commons last night over his plans to extend to 42 days the period that suspects can be detained without charge. He did so dependent on the support of the Democratic Unionists. It was the most hollow of hollow victories.

Here is a Labour government with possibly less than two years left in power. If it loses the next election, the party could be out of power for two terms at least. This summer is the last phase, possibly for a long time, in which a Labour administration can take some risks in order to make a difference to people's lives, to implement policies which make a lasting impact, ones that will generate waves for years to come. Soon all attention will be on the next general election and there will be no space for big legislative moves. By next summer, the general election will be only months away and the appetite for risk-taking, always limited in this government, will be non-existent. Time is running out.

How has Mr Brown chosen to spend these valuable summer days when real power is still in his hands, the pivotal phase before it shrivels to nothing as the next election moves into view? He chooses to use up vast amounts of limited energy and political capital persuading MPs to vote for a measure that may never be used, that may not be practical if any senior police officer wanted to use it and may still be defeated in the House of Lords. He has done so when there is already provision, in the event of an emergency, to extend the period that a suspect can be detained.

As Mr Brown often declares, governing is about hard choices. Of his own volition, he made 42 days the centre of attention during the phase of the political cycle when he was still free to put any policy area in that privileged position. It is the choice that makes him culpable. The arguments on either side of the issue are hedged with contingencies and qualifications. Few institutions are certain of their positions. The political divide was never as great as it seemed. Some police officers are in favour, otthers are against. There are members of the Shadow Cabinet who are instinctively in favour of the Government's position. There are members of the Cabinet who are opposed.

But what is absolutely certain in the confused debates and conflicting hypotheses is that there was no urgent need to legislate this summer. No one was pleading with Mr Brown to bring this policy back to the centre of the political stage. As a new Prime Minister, it was his choice. Of all the things he could have done, he opted for a policy that has lapsed predictably into macho posturing and the opposite – a weak attempt to please everyone, thereby neutering the original machismo.

The absurdity of the contortion was exposed during Prime Minister's Questions yesterday. Mr Brown argued that it was necessary to pass the measure now, during a period of calm, rather than give terrorists the "oxygen of publicity" by rushing to pass an extension in an emergency, which he could do under the existing Civil Contingencies Act. Yet a few minutes later, Mr Brown confirmed that Parliament would be asked to give its assent to an extension in precisely the same way and in the same extreme circumstances under his new proposals.

So all the ministerial huffing and puffing leads to a position that exists already. As David Cameron pointed out in a highly effective series of forensic questions, the proposals represent "ineffective authoritarianism".

No doubt Mr Brown and others will seek to portray the vote as the start of a new phase in his leadership, a hurdle overcome, a popular measure carried in the face of opposition by the Conservative leadership. In a fleeting moment of optimism, he might be tempted to regard yesterday's debate as a return to the glories of last summer. That was the period, seemingly centuries ago, when he was hailed as the solid reliable leader of the nation and when, to use one of his favourite phrases, the Conservatives were often "on the wrong side of the argument".

It will not work like that. Last night's vote is not the route back to electoral popularity. The policy is too muddled. The parliamentary outcome is still unclear in spite of last night's vote. The political dividing lines over it are too fluid. If this is the policy that marks a return to form, I dread to think of the policy that sends Mr Brown back down into a hole.

Only Mr Brown knows the balance in his own mind between expediency and principle that propelled him to make so much of a policy that alarms many in his party and beyond. What is depressingly clear is that the political calculations were misjudged. They might have worked if Mr Brown had still been on something of a honeymoon and planning for an early election. But now he must play a longer game and his government urgently needs a sense of direction and purpose.

This summer he could have taken risks in other policy areas to define his leadership. At least he could have contrived ways in which the focus was placed on areas where his confused administration is making some important changes for the better. Under the surface there are still lots of good policies being almost secretly implemented. Yet, in policy terms, this summer will be remembered most for the battle over 42 days, the "symbolic assault on civil liberties" – as Mr Cameron put it yesterday in another potent phrase. The attack is symbolic because the measures will not make much practical difference.

The shame of it all is that when he was waiting for years to be Prime Minister, Mr Brown did not fantasise about the day he could wield prime ministerial power by locking up people without charge. Much more likely, Mr Brown and his friends would sit in the Treasury until late into the night, discussing issues relating to inequality, the best way of reforming public services, the dangers of Blairite triangulation and the adverse impact it was having on the Labour Party. Yet, in the final summer in which Mr Brown has the freedom to implement risk- taking policies, he comes up with this and he did not need to do so.

Politics is partly about choreography, the issues that are highlighted, the sense of direction that arises from the focus. The Prime Minister has a big pulpit on which to take the lead. It is not easy to do so when there is daily bad news about the economy and other matters, but a leader is always a powerful choreographer.

From his perspective, the best that can be said of this exercise in energy-sapping contortions is that Mr Brown won the vote. It would have been much worse for him if he had lost. But last night's division does not mark the end of a dark period or the beginning of something new. Instead, it has all been a waste of time, energy and power at a point when the Government is running out of all three.