Ian Birrell: Like it or not, the PM has never been stronger. He should exploit it

Since the referendum, the Lib Dems have been a destructive presence, endlessly opposing ideas

When George Osborne addressed Cabinet last week, he compared the proposed deal to salvage the euro and safeguard our futures with a doctor coming upon a patient who had suffered a heart attack and telling him to cut down on eating chips. But in truth, no one really knows if the latest proposed cure for Europe will work or not.

Only one thing is certain: David Cameron is in a stronger position today than he was before he went to Brussels. Not just in his party, where a leader never loved by his troops has suddenly won heroic status by standing up to French intransigence – as shown in yesterday's parliamentary debate. But also in the country at large, where like it or not most people remain hostile to closer European union.

His coalition colleagues, however, look weaker than ever. The Liberal Democrats have endured humiliating reversals on economic strategy, on higher education and on political reform, while they lacked courage to speak out on difficult issues such as immigration. Now if they want to stay in government their exhausted-looking leader must sacrifice his most cherished ideal. Has his party any ideological baggage left to jettison?

Talking to Tory cabinet ministers over the weekend, they repeated the Coalition's mantra that a party is at its strongest when it is weakest. Just as after the referendum reversal on proportional representation in May, the presumption is they must throw their partners a few treats to keep them sweet and ensure the Government remains intact.

No one believes this more than the Prime Minister, who remains committed to coalition government for this parliament. He believes it is in the national interest and that it is vital not to spook tremulous markets, given the fragile state of the economy.

But there is an alternative. Mr Cameron could allow the fissures to widen and hope the battered Liberal Democrats decide enough is enough. For if an election could be provoked as a result, the dissolution of the Coalition would be in the long-term interests of the nation. After an impressive start, the Liberal Democrats have been a crushing disappointment in government. They have lost their nerve along with any sense of what they stand for. Since the referendum they have been a destructive presence, endlessly opposing ideas but rarely offering constructive alternatives. "Always negative, never putting forward anything positive," as one key insider put it.

The only coalition policy a Conservative administration would not have introduced has been the welcome raising of tax thresholds for low earners. The Liberal Democrats have blocked deregulation designed to spur economic growth, stymied decentralisation to increase public participation in politics and opposed vital public-service reform.

Tory modernisation is jeopardised by their coalition colleagues constantly claiming to be saving the nation from the nasty party. Often, their charges are wrong, but the damage is done. To take one random example, it was Mr Cameron who stomped on the idea of reducing the 50 per cent tax rate for high earners, not Liberal Democrats like Vince Cable and Chris Huhne.

Conventional wisdom says voters punish any party that engineers an unnecessary election, especially in such dark days. But this feels like one of those viewpoints that generates great discussion but has minimal effect on outcome. There seems something rather patronising about the idea that, in a fit of pique, voters could not act in their own best interests.

And consider the politics. To the left is a Labour Party with a foundering leader who remains trapped by his past, has failed to connect with the electorate and is stuck with outmoded economic policies. To the right, the headbangers of Ukip have been rendered even more irrelevant than usual. And in the centre, a pygmyish party that has lost any sense of purpose and would be fighting on the basis of closer European ties.

Mr Cameron is not a man scared to take risks, as we saw again last week. He should ponder if it is really worth limping on for another three years with a crippled coalition, held back by a party with liberalism in its genes but panic-stricken conservatism clouding its brain. Surely a government with the mandate and power to transform Britain would be more in the national interest?