When David Cameron became leader of the Conservative party he was determined to avoid a subject that had proved fatal to his predecessors. The European question would not derail his leadership, as it had that of Sir John Major and before him Margaret Thatcher. Isn't it great, he was fond of saying several years ago, that the Tory party isn't having the usual row with itself over Europe.

In the event it turns out that on Cameron's watch it is crunch-time for Britain and the European Union. We will be compelled in the next few years — quite possibly even months — to choose what kind of relationship we want with those in charge of a new hegemony on the continent.

The PM's Major mentor: Cameron has adopted the policy of the last Tory incumbent at No 10, trying to win concessions on Europe but then trundling along behind France and Germany (Dominic Lipinski/PA Wire) 

Much of post-1950s Conservative policy has been predicated on avoiding having to make precisely those kinds of stark choices about Europe. At the heart of it was a very British self-delusion, rooted in the notion that the pro-Europeans running other countries didn't really believe in what they said they believed in. Britain would be "in", but whenever criticism was voiced governments claimed that this was fine because our continental partners were not serious about realising their founding father Jean Monnet's integrationist vision. Or if they were serious, they could be blocked or slowed.

It always was a poor Foreign Office-designed argument at odds with the evidence. Now, after the crisis of the Eurozone it becomes impossible to make the case with a straight face. The grand historical error that was the creation of the single European currency is being compounded by a drive to some form of common economic government by compulsion in the Eurozone.

Cameron, being an establishment figure who has liked to see himself above petty party politics, originally attempted to pursue a policy in line with the pragmatic tradition.