Sometimes it seems like government by paralysis is written into the US constitution. Every time we Americans confront a problem that really needs resolving – like our vast underclass of 12m illegal immigrants, or the almost 50m Americans who have no health insurance, or the risks of global warming – our democracy seems to fracture in the face of it.

Instead of the tyranny of the majority, which our constitution was written to combat, we increasingly seem to suffer a tyranny of immobility. Last week, for example – in spite of almost universal agreement that America’s immigration system is grievously hurting companies, the country and the American dream – the US Congress again failed to strike the political compromise needed to repair its deficiencies. It is enough to make a true democrat despair: ordinary Americans, from both parties, are fed up with the inertia.