Mary Ann Sieghart: If he picks his fights well, Clegg can still deliver for his Party

Talk of what the third party had achieved in power was banned at the start of the Coalition,but is now allowed in the run-up to May's elections

What is the point of Nick Clegg? The Labour MP John Mann asked the Deputy Prime Minister this brutal question in the House of Commons the other day. "Errr ..." was Clegg's less-than-eloquent reply. Yesterday the Liberal Democrat leader tried to persuade his party and the country that he did have a point after all. The BBC showed its disdain by running only a fraction of his spring conference speech live on the News channel and devoting BBC Parliament to a programme on US politics.

Instead of running the same tsunami footage over and over again, BBC News would have done better to broadcast the Lib Dem leader's speech in full. For Clegg actually made quite a strong fist of defending his part in the Coalition. Of course, he didn't get all he wanted on tuition fees, but had he gone into coalition with Labour, he would have faced exactly the same problem. It was Labour that first brought in the fees, and Labour that commissioned Lord Browne to suggest ways of increasing them. As Clegg admitted in his Q&A session with activists on Saturday, the Lib Dems were in a pretty weak negotiating position.

What has cost Clegg a lot of popularity, though, has been his determination to support government policy wholeheartedly. If only he could have been as candid in public as many of his ministers were in private to Daily Telegraph reporters masquerading as constituents. If he could have detached himself a little from the policy, allowing voters to understand that his heart wasn't in it, perhaps they would have forgiven him a little more.

The trouble is that the short-term interests of the Lib Dems collided with those of the country and the Coalition. It is in the national interest that the Coalition should work, that at a time of economic and financial fragility, government is robust. It is also in the Lib Dems' longer-term interest that coalitions shouldn't be seen to be weak. Referring to the hurtling pace of reforms under this government, Clegg joked yesterday: "Perhaps the new complaint about coalition governments is that coalitions are too strong." With the AV referendum coming up, it was critical for the Lib Dems to counter the "no" campaign's most powerful argument: that AV would lead to more coalitions. The coalition brand needed decontaminating just as badly as the Conservatives' did.

But while both parties have had to compromise to make the Coalition work, only one has suffered electorally. You might hear Tory voters complain that their government is not tough enough on Europe or on law and order, but the party has barely slipped in the polls. By contrast, the Lib Dems have lost half their supporters amid cries of hatred and betrayal.

So could Clegg and his party show a little more detachment from their partners? Well, it is starting already. The two leaders have agreed to disagree publicly on values: David Cameron made a speech on multiculturalism recently which was swiftly contradicted by the Deputy Prime Minister. And Clegg's long passages on liberalism yesterday were designed to make the Lib Dems look more distinctive.

Clegg is also embarking on what his team call "positive differentiation" – boasting about what the third party has already achieved in government: the pupil premium, the AV referendum, the Freedom Bill, and so on. This sort of talk was forbidden at the start of the Coalition, but is now allowed in the run-up to May's local elections. As one of Clegg's advisers told me yesterday, "The ship has to be stable before you can start rocking it a bit."

Negative differentiation is still verboten, though we might see some of it later in the Parliament. This is when the Lib Dems start saying: "By being in government, we've managed to stop stuff from happening." It might be preventing the Conservatives from being too Eurosceptic, thwarting a more right-wing agenda on law and order, or stopping ministers being rolled over by City interests.

The Tories are aware that they are going to have to give the Lib Dems four or five big wins that they can boast about at the next election. If the AV referendum is lost, Clegg will be guaranteed a crack at House of Lords reform. More pupils from poorer backgrounds will have to win university places, "even if it means kidnapping the Chancellor of Oxford and holding him hostage in a castle," joked one Tory Cabinet minister yesterday. Beyond that, the Lib Dems will have to choose priorities from a list that includes greenery, civil liberties, tax reform, banking reform and measures to spread any economic recovery beyond the South-east.

How much dissent can the Coalition stand, though? Well, the Blair government was racked by disagreement, though it was usually personal grievance masquerading as ideological difference. Sometimes there wasn't even an attempt to dress up the arguments as ideological. There were feuds not just between Gordon Brown and Tony Blair but between Brown and Robin Cook, Brown and Peter Mandelson, Brown and Alan Milburn. Spot a pattern there?

In this government, by contrast, the remarkable thing is how well most of the players get on. Even they find it remarkable. So when they argue over policy, at least there is genuine political disagreement. And voters are sensible enough to understand that two parties governing together are not always going to have the same views.

The biggest immediate test is over the NHS reforms. The Lib Dems voted against the Health Secretary Andrew Lansley's plans at the weekend. Not a single Lib Dem minister to whom I have spoken recently has expressed any enthusiasm for them. Mind you, very few Conservatives have either. David Cameron, while keen on the policy, knows that the politics of it are dreadful.

So this presents a rather convenient opportunity for both coalition parties. Clegg can tell Cameron that the reform must be delayed or watered down to satisfy the Lib Dems. Most Tory MPs would be genuinely relieved if this were done. The junior coalition partner would look to the country as if it were saving the NHS from unpopular Tory measures. And Downing Street would have an excuse to row back.

That's the point of Nick Clegg. As long as he chooses his battles carefully, he genuinely can make Tory policies better.

m.sieghart@independent.co.uk

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