This combination of British flexibility with European scale is obviously a powerful one. Although I sometimes read that the City is “drowning” or “suffocating” in regulation, London seems to be in fairly rude health. Over the past decade, the surplus from Britain’s trade in financial services more than doubled, from £23 billion in 2004 to £58 billion in 2014. And last year, once again, London was rated by the Global Financial Centres Index as the world’s most competitive financial centre. So under the present set-up, something seems to be going okay.