And so, the inevitable has happened. On Sunday, Iran made good on a threat it had made in May and announced that it will break a set limit on uranium enrichment in breach of the 2015 agreement clinched by the Barack Obama administration, and with the participation of key European powers. The deal had always been in danger ever since the United States, under President Donald Trump, unilaterally withdrew from it last year. After months of open and quiet diplomacy failed to convince Washington to reverse its decision, Teheran said two months ago that it would, in 60 days, step up production of enriched uranium, the key ingredient for fuelling energy reactors that is also used to build nuclear weapons.

Iran's risk-filled decision was aimed not so much at the US, but as a pressure point against the Europeans - France, Germany, Russia and Britain (China was the other nation involved) - who were signatories to the deal but who could not find ways to help Iran tide over the crippling effects of re-imposed sanctions that had been partially eased since 2015. It was made after the two-month deadline Iran gave to the other signatories. While optically alarming, it is still a calibrated game. Officials said in the past that the enrichment level would go up from 3.67 per cent to about 5 per cent. It does not yet take Iran anywhere near the 90 per cent concentration of enrichment required for making a bomb.