Cui bono? When the economic cycle does its inexorable work, and a recession strikes the US, which political force will benefit? What the question lacks in taste, it more than makes up for in importance.

It is also a nightmare to answer. To understand the opacity of the link between economics and politics, recall the last crash. A fiasco that was made in the private sector and eased by the state should have been the left’s biggest opening since the Great Depression elevated Franklin Roosevelt. Barack Obama was duly elected president. John Maynard Keynes became a pop-culture icon from beyond the grave. But the moment fizzled. The lasting products of the crash were instead the Tea Party movement and the presidency of Donald Trump.

Going into the next recession, the principal forces in the US are his populist right, the populist left of senators Bernie Sanders and Elizabeth Warren and — as frail-seeming as its champion, Joe Biden — the old centre.