John McCain may have tried to cast Iran as Barack Obama’s first foreign policy failure, but America remains overwhelmingly behind the President, rejecting the pressure to weigh in further on the post-election crisis.

More than half of Americans — 56 per cent — believe that Mr Obama’s pitch has been perfect, according to a CNN poll, and three out of four oppose any direct interference from Washington in Iran’s disputed election result.

The findings will come as a relief to the Obama aides who spent the weekend scrambling to defuse Republican criticism that the President had failed to speak out strongly enough against Tehran.

However, the challenge to Mr Obama’s plan to engage Iran is far from over. The strategy could still go badly wrong as the world waits to see what Tehran will do next in pursuit of its nuclear ambitions.

Bluster from Mr McCain, below — contrasting Mr Obama’s reticence over Iran with Ronald Reagan’s forceful attack on the Soviet “evil empire” — came from another era and his criticisms have largely fallen on stony ground.

“I think the Administration has played it about right so far,” Suzanne Maloney, a senior fellow at the Saban Centre for Middle East Policy at the Brookings Institution, said. “But this is not about what’s happening here, it’s about what’s happening on the ground there. No one could say the context for negotiations has changed dramatically. I am not optimistic.”

Mr Obama admitted last week that prospects for a dialogue “had been dampened by the brutal crackdown”. The invitation to attend multilateral talks in Paris remains on the table, but the prospects for direct bilateral talks look dim.

The issue for the outside world, as Mr Obama reiterated last week, is not the election but the “ticking clock” of Iran’s progress towards a nuclear weapon. Israel could be the beneficiary as Iran behaves ever more like the demon that the Israelis insist it is.

At the same time, Iran’s behaviour could isolate it still more. Russia and China may be unmoved by electoral fraud but may not wish to be on the wrong side of history. What Mr Obama decides to do next may determine whether he is, too.

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