There is nothing like a crisis to discover its real roots. At the surface level, boiling furiously, the outcome of the Presidential elections in Iran, which returned the irascible Mahmoud Ahmadinejad to power, was immediately contested by his opponent, Hossein Mousavi. Massive demonstrations reminiscent of the turbulent period leading to the overthrow of the Shah in 1979 and the birth of the Islamic Republic under the rule of a Supreme Leader, Ayatollah Khomeini, followed.
Mr Ahmadinejad election to the Presidency, first time round, was owed in great part to the backing he received from the Supreme Leader, Ayatollah Ali Khamenei. Whether or not the President has the Ayatollah's blessing for the strident stance he has been taking on the matter of nuclear development the latter's endorsement of Mr Ahmadinejad's victory last Monday - he called it a "divine verdict" - was publicly questioned by scores of thousands of Mr Mousavi's supporters. It also raised the temper of the crisis considerably.
During this unfolding drama, Mr Ahmadinejad, with a sang-froid that must have been the envy of all beleaguered leaders throughout history, took himself off to Moscow. There he was met, smiles all round, by Russian President Dimitry Medvedev. His absence from the capital at that delicate moment received little or no comment from the international English-speaking media, which had its mind concentrated on what it was describing as the internet/Twitter revolution.
If one is to comprehend the complexity of what is at stake in Iran, it helps to focus on the idea of an equilateral triangle threatening to implode. At the apex there is the Ayatollah, the Supreme Leader; at the base the two contenders for the Presidency, Mr Ahmadinejad on one side and on the other, Mr Mousavi. To dismiss the chances of the latter is to disregard Mr Mousavi's powerful backer; does Akbar Hashemi Rafsanjani ring a bell?
His power lies in the fact that when the first Grand Ayatollah died, he played a key role in getting Mr Khamenei promoted to Supreme Leader. Apart from that, Mr Rafsanjani scaled formidable heights when Mr Ahmadinejad defeated him in Presidential elections, four years ago. These included the powerful chairmanships of the Expediency Council and, more disturbing for the Ayatollah, the Assembly of Experts, which has the power to select and de-select the Supreme Leader.
With these two powerful men taking sides, the drama has taken on an intense dimension. Its denouement depended on what the Ayatollah said, and did, yesterday, when he addressed the nation after Friday prayers at Teheran University. There were two choices open to him: to crack down on the demonstrators or to offer some form of conciliation. He chose to stamp the imprimatur of legitimacy on Mr Ahmadinejad, refused to consider fraud was possible in the Islamic Republic, blamed America and Europe for the unstable situation brought about by the poll (naturally; the more ominous interpretation of this for Mr Mousavi is that the protests have the blessing of the enemy) and called on the opposition to accept that divine verdict - or face the consequences.
Today we will know whether Mr Rafsanjani and other powerful elements siding with the opposition will come to heel or whether Mr Mousavi's supporters will take to the streets and risk a bloodbath, as indeed they have been doing all week. Either way, the crisis has shown up dangerously deep cracks in the Iranian political edifice. And the fist Barack Obama asked Iran to unclench, remains firmly clenched.