Germany risks an economic war on three fronts at once. The combined shocks would endanger the post-War miracle, and expose the underlying fragility of an ageing nation with 20th Century industries.

Donald Trump’s 20pc tariff on European cars is likely to come into force this autumn, shutting up to half a million German vehicles out of the US market.

This could happen just as Italy’s Lega-Five Star insurgents force a budget showdown with the EU, threatening to set off a chain of events that ultimately leads to euro rupture and a Lex Monetae default on vast German credits.

Both sagas may well intrude before the final Brexit summit in October. A "no deal" breakdown would then start to have an existential feel for Germany. Its car industry sells 770,000 vehicles a year to the UK, more than to the US and China combined. Britain is their profit cash-cow.

There might be a spontaneous "patriotic" boycott of German cars by UK consumers in such circumstances. Tariffs each way, plus "rules of origin" requirements, would break Volkswagen’s and BMW’s supply chains. They would have to switch from Continental to UK subcontractors as fast as possible to protect their sunk costs in UK plants.