Yet the logic of Britain's exit is looking ever harder to resist. The EU is institutionally dedicated to the idea of ever closer union, regardless of what its citizens actually want. For too long, the U.K. has deluded itself that this can change. Even now, Cameron is trying to make the case that it can, and that the U.K. can direct the operation. Enough, already.

The alternative to ever-closer union or Britain's full-frontal exit is to negotiate a new semi-detached status. Fortunately for the U.K., it has already anticipated this course by standing aside from the ill-fated euro project. Rather than trying to persuade the EU as a whole to change course, Cameron should concentrate now on developing a more comprehensively conceived associate status. That would be better for both the U.K. and the EU than outright divorce -- though Cameron may have to threaten a complete separation, and be willing to do it, to get the rest of the EU to go along.

That will be quite a gamble. The U.K. could undoubtedly prosper as a close associate of the EU -- as a partner in an enhanced free-trade area -- but would pay a crippling price if it left the union in anger and suffered retaliation on trade policy and other issues of mutual interest. If the U.K. government is unwilling to face that risk, the defeat it suffered in the past few days certainly won't be the last.

For years, Britons who supported the European project argued that the country's interests would be best served by engaging fully with the EU in order to guide and improve it. That was both arrogant and naive -- arrogant because it assumed that the U.K. was entitled to wield disproportionate power, naive because it assumed the rest of the EU would let it. That delusion should now be abandoned.

This doesn't mean embracing the equally delusional idea that Britain can afford to be on unfriendly terms with the rest of the EU: The costs of an angry split, if it comes to that, would be enormous. Still less should it mean adopting the chauvinism and xenophobia of the anti-EU populists. But the gap between what the U.K. wants and where the EU is headed is just too wide. And it's time, finally, to admit that it won't ever close.

David Fuller's view

This is a very good summary of a difficult situation.  I see little chance of the UK being able to influence the EU’s course, which has always been to create a United States of Europe, although in reality it would inevitably be quite different from that.  I also question whether the EU is in any mood to consider the UK “as a partner in an enhanced free-trade area”, as this would set a precedent for other countries to consider. 

Nevertheless, I would like to see Cameron and the leaders of other UK parties actively negotiate for a new semi-detached status for the UK, against the background of a fixed date for an in / out referendum on our EU membership, if our negotiations are unsuccessful.