The Bush administration has opted for a grand plan to contain Iran rather than trying to reach a grand bargain with its government. It is convinced Iran is an aggressive and destabilising force in the Middle East directly opposed to US interests there. Elements of the plan have been laid out in recent weeks and are now feeding into its overall approach to the region and to the war in Iraq.
Major new arms deals with conservative Arab regimes and Israel, renewed United Nations sanctions against Iran and the convening of a meeting to restore negotiations between the Israelis and the Palestinians are part of a comprehensive approach now in place.
The suggestion that the US should reach a "grand bargain" with Iran arose from discussions on the report by the cross-party Iraq Study Group last November. The report said diplomatic engagement with all Iraq's neighbours is required if that state is to be stabilised. Arising from that it is argued that Iran, as the main regional beneficiary of the Iraq war, would require a security guarantee from the US that it would not be attacked if it abandons its nuclear ambitions, renounces terrorism and agrees not to interfere in Iraq.
Such an initiative has proved a step too far for the Bush administration. Instead it decided to mount the military surge currently under way in Iraq and attempted to find an internal political solution there. It refused to link the Iraq issue with Iran's nuclear one, even though Iraq's neighbours, including Iran, have been invited to discussions on its future.
Iran for its part has defiantly refused to comply with demands from the United Nations Security Council that it cease work on those parts of its nuclear programme that would enable it build a nuclear weapon. It has engaged in protracted and fruitless negotiations, notably with the European Union troika of France, Germany and Britain. They have little choice now but to press for increased sanctions to bring about Iranian compliance through realistic negotiations. The alternatives are to do nothing or accept that force must be used. The US has gone along with these negotiations while keeping the military option open in a debate that has divided the administration between those favouring the diplomatic and military routes.
The issue will come to a head over the next year. Last week US secretary of state Condoleezza Rice announced a major programme of arms deals for the region in an effort to bolster conservative Sunni Arab states opposed to Iran's growing influence - abandoning previous US efforts to spread democracy from Iraq. This is coupled with a fresh effort to address the Israeli-Palestinian issue.
An attack on Iran would stir up even more animosity in the region, put oil prices through the roof, disrupt the whole world economy - and probably set back its nuclear programme by only a few years. If it is to be avoided a real effort must be made by EU and Middle Eastern states to make sanctions work effectively, along with political initiatives that can convince Tehran to co-operate.