David Cameron wants Britain to play an integral role in reforming the European Union. He really does. His speech in Davos today  explained how he is committed to reviving the continent's flagging economies with an agenda for boosting growth - deregulation; liberalisation, competitive taxation.
This is a familiar tune. Britain's position under Labour wasn't so very different - accepting a degree of political integration as the necessary price for creating an open, free trading space of continental scale and hoping, over time, to make that space look more like the UK economy and less like the French one.
The problem now, as I wrote in my column this week , is that the kind of diplomacy that is required actually to drive that agenda in the European Council - involving compromise, long-term nurturing of relationships with EU leaders; demonstrations of commitment to the European project - is also the kind of behaviour that the Conservative party generally finds unacceptable in a leader. In other words, Cameron can say this stuff, but he is no closer to getting it done if he can't build the strategic majorities among fellow EU member states to make it happen.
But there is another problem. Cameron's analysis of the EU's growth problems necessarily has to exclude discussion of the effect on demand of choreographed mass austerity - to concede that point would be to admit that the same force is in play in Britain. But clearly this is an issue. In his speech, the Prime Minister praised efforts by eurozone countries to bring their public finances under control - the drive for a fiscal compact led by German Chancellor Angela Merkel - but warned that it was not enough. He encourages the single currency bloc to consider issuing euro-bonds and effecting transfers between states - a true fiscal union, in other words. He essentially told Merkel to dip into her budget to save the euro.
If Cameron understands the inadequacy of Merkel's plans at the level of budget imbalances inside the eurozone, why does he not understand the related problem of German-enforced austerity for the continent draining aggregate demand? Why does he insist on offering only long-term supply-side solutions to the problem of European growth? The answer, I suspect, is that the government does understand the issue but it is taboo because of the coalition's political commitment to make austerity a morally inviolate part of domestic economic policy.
There was a meeting last week of the Franco-British Colloque  - a top-level club of politicians, academics, business leaders etc to discuss cross-channel issues. It meets annually and this time the gathering was held in the UK. George Osborne was there and, someone who was present tells me, in the discussions of the EU's growth problem, the Chancellor effectively acknowledged the macroeconomic case against collective European austerity. He simply couldn't accept that it was relevant to the policies he is deploying in Britain. Treasury economists will surely be telling him the same thing: Merkel's fetish for fiscal conservatism is going to drag Europe down.
If Cameron wants to take a lead in promoting growth in Europe he could start by making that point. He can't of course, at least not without repudiating the central tenet of his government's economic policy.