During his campaign, in effect, Mr Obama promised to be the constraint: to oversee Congress and guide it with a moderating hand. That was the difference he promised to make. There were always going to be limits to what he could do, but his failure so far even to try has been total.

He has let nearly every agenda be set by the Democrats’ left-leaning congressional leadership. This comes in a country in which 40 per cent of voters call themselves conservatives, 36 per cent moderates and 20 per cent liberals.

Voters are confused and concerned about the policies coming forward " above all by their mounting cost " but he has made little effort to explain or reassure, let alone influence. He has chosen to act as cheerleader for whatever congressional Democrats cook up.

On healthcare, Mr Obama stood aside during months of chaotic haggling in Congress. By the summer, unsurprisingly, voters opposed to reform outnumbered voters in favour " again, above all, expressing worries . . .

. . about the cost.

In recent days, the House took up a bill even more expensive than previous proposals, with features especially provoking to moderates. It even alarms many Democrats – hence the 39 defections in Saturday’s vote. Nothing in this inspires public confidence. Yet Mr Obama expressed no reservations, applied no pressure: he blandly endorsed the bill.

More columns at www.ft.com/clivecrook