Cameron has focused on the small view of local politics and party unity, failing to grasp the future necessity to perform a volte face. When it comes to it, it will probably not be his face signing up to an inevitable new Treaty, and there is no conceivable way in which the other EU States will exempt the UK from financial services regulation at a later date. The City of London may rejoice today, but it will pay.
The deeper irony is the financial markets are more innovative than hamstrung prime ministers. Had Cameron accepted the unity of Europe and pulled back from a veto, the City would have found a way to innovate and grow. And the price? Already it is being paid, by the City of London. This was no confidence trick, though Cameron's strategy is founded on illusion.