A US-Iran rapprochement cannot be rushed

The risk of misunderstandings, especially on the American side, is great

In the end, neither happened. Barack Obama did not hold the one-on-one meeting with the new Iranian President, Hassan Rouhani, that had tantalised the world’s media. Nor did the two leaders come close to shaking hands. But after more than 30 years without diplomatic relations, those omissions might be for the best.

There remains great hurt on both sides, and a gulf of understanding – especially in the US – left by having no official representation in Tehran for the best part of two generations. Compared with Iran, the US is an open book. The risk of misunderstandings, especially on the American side, is great. It would be little short of tragic if the early signals from Tehran were misread, and so squandered.

It was apparent, from their respective speeches at the UN General Assembly, that both leaders were treading carefully. After all, they had their own public opinion to consider, as well as the expectations running so high elsewhere. Mr Rouhani’s insistence that Iran “poses absolutely no threat” need not be taken at face value; any threat is in the eyes of the beholder. But his stated readiness to engage in “results-orientated” talks on his country’s nuclear programme, and his disclosure that he has negotiating authority, delegated from the Supreme Leader, raise hope. Mr Obama would be derelict if he did not now try to test them out.

The rewards from improved US-Iranian relations, let alone – dare one hope? – agreement on the nuclear issue, could be far-reaching. Iran would be brought in from the cold at a crucial time. The regional map, which looks increasingly hostile to the West, would seem a little friendlier. The stakes are so high that it would be foolish for either side to scupper a deal by rushing. It must be steady as she goes.