On Wednesday evening, a familiar crowd of City grandees and executives gathered at the annual winter drinks party thrown by Finsbury, the PR firm run by the arch-Remainer and People’s Vote chairman Roland Rudd. Sir Roger Carr, the chairman of BAE Systems, Chris Gibson-Smith, former chairman of the London Stock Exchange and Lord Myners, the former City minister, were among those mingling beneath the Tate Britain’s high ceiling as waiters bustled around, carrying trays of champagne.

The mood was generally upbeat, even though the guest list was heavy with big-company representatives who had campaigned for Britain to remain in the EU. Most agreed they could live with the compromise deal unveiled by Theresa May that morning after months of haggling and uncertainty.

It didn’t take