The rise of the UK Independence Party, once dismissed by the Tory modernisers as an utter irrelevance, has not helped. Not all those members who leave defect to UKIP, but MPs report that a sizeable number of once Tory voters have done so. UKIP and its ebullient leader Nigel Farage may be coasting a tidal wave of discontent with the conventional parties which will diminish as the next general election approaches. But even if UKIP's popularity recedes, it has only to poll six to eight points in a general election to cause havoc. Conservative MPs with small majorities understand that an extra couple of thousand votes for Farage's troops in their constituencies will split the vote and let another party through. 

Is the Tories' UKIP predicament remotely fixable? It seems doubtful. The European dilemma looks unresolvable. The Prime Minister's speech in January was a thoughtful, well-constructed attempt to build a position around which Conservatives of all persuasions might rally. Those who want to get out of the EU have their promise of a referendum if the Tories somehow win the election; those who want to renegotiate the terms of British membership of the EU are catered for and pro-Europeans will be able to campaign to stay in if it comes to a vote. This sensible compromise seems barely to have registered. Defecting voters either did not notice the Cameron shift on Europe, or if they did discounted it as another meaningless promise. Polling suggests anyway that many of those switching to UKIP have become unpersuadable. They are simply furious with the class running the nation's affairs, and that includes some Conservatives looking for a way to rebel.

Some of the erstwhile Tory modernisers seem to understand the scale of the potential crisis. Discreet efforts are being made in Parliament to reach out to all but the most irreconcilable critics of the leadership, although others — such as Nick Boles — continue their crusade against Conservatives sceptical of the modernising project. Meanwhile, George Osborne wants — somehow — to get the Tory tribe to forget its differences and concentrate on a common enemy. It is a little late for that, even though the prospect in two years' time is a Labour government, staffed by many of those who did so much to land Britain in the mire.

The Tories' situation is a mess. The challenge facing British Conservatives is still the same as it was when a fresh-faced 38-year-old leadership contender paced the stage in Blackpool in early October 2005. That day David Cameron's speech, delivered without notes or autocue, won him the party leadership election. Rereading it one is struck by how optimistic and inclusive — in the best sense of the word — it was. He seemed to want to marry more traditional Conservative themes on education and the economy with a modernised worldview. "We can be that new generation, changing our party to change our country," he said. "It will be an incredible journey. I want you to come with me."