It would only encourage irresponsible lending. Deficits would run out of control. The rules of the single currency would be undermined, and voters would lose faith in the euro. Over the last few years, the Germans, the European Central Bank, and the EU itself, have been adamant that banks shouldn’t be bailed out inside the eurozone. Along the way, Greek, Cypriot, Italian and Irish banks have all been allowed to go to the wall or squeezed to extinction.

But hold on. There seems to be an exception to that austere financial regime. Big German banks. With the once mighty Deutsche Bank in serious trouble, it turns out there is nothing wrong with the government orchestrating what amounts to a rescue after all.

In the years since the eurozone crisis first blew-up in 2011, German policy-makers have insisted that bank bailouts would only make matters worse. When Italy, for example, stepped in to merge two failing banks in 2017, the former German finance minister Wolfgang Schaeuble was quick to argue the rules designed to make sure ‘that taxpayers will never again carry the risk of banks’ should be enforced.

In Cyprus, in 2013, banks were allowed to close and depositors with more than 100,000 euros were forced to suffer losses, largely at the insistence of the Germans. In 2015, the Greek banks were closed for more than a week, at the insistence of the German Chancellor Angela Merkel while over the last year Germany has led the opposition to a banking union for the eurozone that would protect depositors. Again and again, the message from Germany policy-makers has been the same. Banks and their shareholders should be left to look after themselves.

You can argue about whether that is the right or the wrong decision. But you can’t really argue about whether it should be applied consistently. And yet, that doesn’t seem to be the case. It has become painfully clear for the last year that Deutsche Bank, once the most important financial institution in Europe, might need a rescue. Its share price has fallen 90 per cent in a decade, and halved in the last year alone. In response, the government in Berlin is now orchestrating a merger with its main rival Commerzbank. More interestingly, the state will end up with a stake in the new entity via its 15 per cent shareholding in Commerzbank, and it may well inject extra funds in to support the merger through a new fund being created to back ‘national champions’.

That lays bare a stark truth about the eurozone, and indeed the EU. There is one rule for Germany, and another for everyone else. In truth, if it is in as much trouble as it appears to be, then Deutsche Bank should be allowed to go under. After all, its depositors could be protected, and its debts placed into a ‘bad bank’ and gradually wound down. That is what most German policy-makers would recommend for other countries, along with lots of warnings about the threat to the viability of the single currency if the profligacy and rash lending had no consequences. If the German government wants to use taxpayers money to create a state-backed ‘national champion’ bank that’s its decision. It will probably end up failing anyway, just like ‘national champions’ in most other industries. But it can hardly complain if other countries within the eurozone notice that all the talk of ‘responsibility’ and ‘financial caution’ applies only to others, and not to Germany itself – and end up very disillusioned as a result.