True to his word, President Obama has now come up with a direct offer for "a new beginning" in American-Iranian relations. His video message yesterday, released to coincide with the Iranian spring festival of Nowruz, was radical in its form and emollient in its language. No one expects a single video by an US president to transform Iran and America into bosom allies. Indeed, judging from the initial reaction by Tehran's leadership, it may not produce much immediate response at all.
But coming after the uncompromising rhetoric of the Bush years, when Iran was castigated as a promoter of terrorism in the Middle East and a rogue state bent on developing nuclear weapons, the tone of Mr Obama's message is a positive turnaround in language. And after the years of isolation and sanctions which the Bush administration ratcheted up with its European allies in an effort to get Iran to stop all uranium enrichment, President Obama's readiness to move from threats of military action to solid diplomacy is nothing short of revolutionary.
On the specifics of Iraqi security after US withdrawal and Afghanistan reconstruction, the scope for co-operation between Washington and Tehran is considerable. Iran has obvious interests as well as influence in post-war Iraq. The same is true in Afghanistan, where Iran has always been a bitter foe of the Taliban. Even before Mr Obama was elected, the Bush administration was moving to an accommodation with Iran on these issues. Now that Mr Obama is proceeding with troop withdrawals from Iraq and a new policy consideration in Afghanistan, those tentative dealings could be upgraded.
Here is where the caveats come in, however. A "new beginning" offers up a host of possibilities that were previously closed, but it does not bring about a breakthrough in itself. And when it comes to Iran's nuclear ambitions, matters become more difficult and more urgent. Tehran's leaders have consistently denied they intend to manufacture a nuclear weapon, but have been adamant over their right to pursue civilian nuclear power. Washington, and its European allies, distrust the assurances and have demanded a halt to all enrichment. And so the question has been stuck in a cul-de-sac of threat and isolation.
There is nothing in Mr Obama's message that suggests a change in this policy. Given the pressures of a Congress eager for signs of weakness in the new President, Mr Obama has probably little choice but to tread carefully. Even if he wanted a quick breakthrough, the Iranian political situation might well make that impossible. Presidential elections take place in June and campaigning has already started in earnest, with President Ahmadinejad under considerable pressure thanks to his poor economic record. No one can be quite sure whether the reformers have a chance of regaining the post and whether the recent withdrawal of their most popular candidate, the ex-president Mohammad Khatami, is a blow to their cause or could help by reducing the number of reformist candidates on the ballot.
Iran's opaque system of theocratic rule means it is not an easy country to deal with. And the recent arrest and detention of the American journalist Roxana Saberi shows how far Iran is from being ready to join the international fold.
But this country is too important to be ignored. And it has too much to offer the wider region to be kept isolated. If Mr Obama's message does indeed provide a new beginning, it can only be for the good.