Lottery winners always promise that wealth won’t change them, only to go loopy before long. The remaining $350bn of Troubled Asset Relief Programme money is having the same brain-addling effect on US policy makers. Worse, the debate has turned sharply political. Even Lawrence Summers, the director-designate of the National Economic Council, seems to have embraced populist soundbites.

In yesterday’s letter to Congress, demanding that the second tranche of Tarp money be handed over forthwith, Mr Summers’ argument shows how quickly one of the world’s great economic minds can downsize to fit Washington. Yet, this is not the time to stoke the Wall Street versus Main Street fire. And it is wrong and unfair to oversimplify the problems America is suffering by blaming only banks. Homeowners and small businesses are not entirely innocent in this global crisis. Nor should governments overplay their ability to halt house price declines or to save jobs.