The conclusion of a nuclear deal between world powers and Iran this week marks a historic turning point in their relations. The six world powers - the United States, Britain, France, China, Russia and Germany - have acknowledged Iran as a regional power with legitimate national interests, which include economic interests that are now stymied by international sanctions. They have accepted effectively that regional powers such as Iran ought to also act as stakeholders of the global order in a transitional phase of world history in which no single conglomeration of countries, no matter how powerful it is, can ensure peace and stability all by itself. This is true certainly of the Middle East.
What has contributed to this recognition of reality is the reconciliation between the United States and Iran, whose relations were ruptured by American support for the Shah, who was overthrown in the revolution of 1979. Combative decades later, Iran is being rehabilitated into the strategic fold by US President Barack Obama's desire to get the two countries out of the rut of the past. The essential condition for his gesture is that Iran must abjure the temptation to develop nuclear weapons. The message is that Iran per se is not a threat, its nuclear weapons would be. A fundamental reason for that reading is that a nuclear Iran would upset a fragile equilibrium involving other regional powers, like Israel, Saudi Arabia and Turkey.
The onus is on Iran now to keep its side of the bargain. It would not be in its interests to run circles around the International Atomic Energy Agency in order to pursue a nuclear weapons programme on the quiet, because any indications of deceit could lead to the restoration of sanctions. International inspections will hold Iran to high standards of scrutiny. Importantly, Teheran must recognise that there are political constituencies in Washington and elsewhere which remain deeply suspicious of its ultimate intentions. The sorry fate of Iraq is a reminder of how the misplaced defiance of an inspections regime contributed to the nation's unravelling, although no weapons of mass destruction were found finally.
The nuclear deal offers Iran an opportunity to play a responsible role in an unstable region. It could do this by moving beyond its self-perception as a Shi'ite power contending for shifting supremacy with Jewish Israel, Sunni Saudi Arabia and secular Turkey. As much as these countries are, Iran is under threat from the rise of the ISIS, a revisionist and irredentist group devoted to the viciously violent overthrow of the constitutional order in the Middle East and beyond it. Iran would serve its own long-term interests, along with those of other countries which cannot gain by subverting it, by acting as a bulwark of stability against the supranational forces of anarchy. Nuclear weapons would not do the job.