It is a decade since the first tremors of what would become the Great Financial Crisis began to convulse global markets. Across the world from China and South Korea, to Ukraine, Greece, Brexit Britain and Trump’s America it has shaken our economy, our society and latterly our politics. Indeed, it has thrown into question who “we” are. It has triggered both a remarkable wave of nationalism and a deep questioning of social and economic inequalities. Politicians promise their voters that they will “take back control.” But the basic framework of globalisation remains intact, so far at least. And to keep the show on the road, networks of financial and monetary co-operation have been pulled tighter than ever before.

In Britain the beginning of the crisis was straight out of economic history’s cabinet of horrors. Early in the morning of Monday 14th September 2007, queues of panicked savers gathered outside branches of the mortgage lender Northern Rock on high streets across Britain. It was—or at least so it seemed—a classic bank run. Within the year the crisis had circled the world. Wall Street was shaking, as was the City of London. The banks of South Korea, Russia, Germany, France, Belgium, the Netherlands, Ireland and Iceland were all in trouble. We had seen nothing like it since 1929. Soon enough Ben Bernanke, then chairman of the US Federal Reserve and an expert on the Great Depression, said that this time it was worse.

But the fact that the tumult assumed such spectacular, globe-straddling dimensions had initially taken Bernanke by surprise. In May 2007 he reassured the public that he didn’t think American subprime mortgages could bring down the house. Clearly he underestimated the crisis. But was he actually wrong? For it certainly wasn’t subprime that brought down Northern Rock. The British bank didn’t have any exposure in the United States. So what was going on?

The familiar associations evoked by the Northern Rock crisis were deceptive. It wasn’t panicking pensioners all scrambling to withdraw their savings at once that killed the bank. It wasn’t even the Rock’s giant portfolio of mortgages. The narrative of Michael Lewis’s The Big Short, of securitisation, pooling and tranching, the lugubrious details of trashy mortgage dealing, the alphabet soup of securitised loans and associated derivatives (MBS, CDO, CDS, CDO-squared) tell only one part of the story. What really did for banks like Northern Rock and for all the others that would follow—Bear Stearns, Merrill Lynch, Lehman, Hypo Real State, Dexia and many more—and what made this downturn different— so sharp, so sudden and so systemic, not just a recession but the Great Recession—was the implosion of a new system not just of bank lending, but of bank funding.