Forget Theresa May cavorting across the Tory conference stage to Dancing Queen. The prime minister is about to try an even more convoluted manoeuvre. She will attempt to get the French president’s support for a compromise Brexit deal that Tory MPs can vote for.

If she succeeds, Britain is heading for Common Market membership in all but name. If she fails, May will be lucky to avoid the sack.

The Abba hit with most resonance over the next couple of months, as Brexit negotiations reach a climax, will not be Dancing Queen but Waterloo, recorded in 1973 when Britain joined the European Economic Community. The lyrics speak of the impossibility of escape and of Napoleon’s surrender.

On Brexit, May needs Emmanuel Macron, France’s