By Matt Frei
BBC News, Washington
On Sunday morning there was a demonstration outside the Iranian Interest section here in Washington, billeted in the Pakistani embassy.
Anti-Ahmadinejad protesters in Washington were divided
Two rival groups of Iranian-American protesters were shouting at each other about the election results.
They both hated President Mahmoud Ahmadinejad, but one group also hated his main rival Mir Hossein Mousavi, calling him a stooge of the ayatollahs.
They fought over which flag should represent Iran, the current one introduced by the Islamic Republic or the previous one, used by the Shah.
On the other side of the country, Los Angeles happens to be the biggest Iranian city outside Iran - 800,000 Iranian-Americans live in southern California.
"Tehrangeles" boasts no fewer than 20 satellite TV stations for exiles, beaming a mixture of subversion and entertainment into their former home country.
Meanwhile, Reza Pahlavi - the former Crown Prince, who would now occupy the Peacock Throne if his father the Shah had not been deposed - sits in a makeshift radio studio above the garage of his mansion on the outskirts of Washington.
Like an immaculately dressed amateur radio ham, he is also busy broadcasting, berating his ex-subjects to fight for democracy.
Unifying the Iranian opposition in exile and at home has been like herding cats.
This division had been one of the greatest assets of the regime. Whether by intent or by default, the fragmentation of opinion and allegiance was nurtured under a regime that became expert at the light hand of repression.
Iran is a country with a serious multiple personality disorder. What we are seeing in these days of turmoil is the therapy
When I was in Tehran in 2002, I interviewed a prominent newspaper editor.
Ten journalists were working out of a small office. The walls were almost bare and the seats were still covered in plastic.
"Why not get rid of the plastic?" I asked.
"No point," the editor said. "We have to move every three months. The government keeps closing us down. So we just shift to a new office with the same furniture, open our newspaper with the same staff, the same types of articles just under a different masthead and name."
There are so many conflicting images of Iran: the hardcore Shia faithful in Qom, the religious capital, beating themselves with chains in memory of the Imam Ali, while muttering "Death to America".
The leading cleric whose office was adorned with that most basic item of the Great Satan school of Interior Design, the Stars and Stripes doormat.
The same man then asked my Australian cameraman to stay behind after the interview for a "private chat".
"What did he want?" I asked Darren, who was smiling.
"He asked me why I was wearing an earring - and whether that meant I was a member of the homosexual tribe."
Iran is a country with a serious multiple personality disorder. What we are seeing in these days of turmoil is the therapy.
Mr Obama is treading a fine line in his response to the Iranian situation
It has come in two ways.
The first is courtesy of President Ahmadinejad. His populism may go down well in large parts of rural Iran. In fact, some intelligence officers in the US believe he may have actually won the election. He then made the mistake of inflating the margin.
Mr Ahmadinejad's populism and alleged cheating has outraged educated Iran, which as it happens, is a huge constituency (Iran has one of the highest rates of higher education in the Middle East).
His knee-jerk anti-Americanism has insulted the intelligence of these people, while his economic incompetence has produced petrol queues in a country that is one of the world's leading producers of the stuff.
The powerful bazaaris hate him for raising the sales tax and his "America be damned" isolationism has imperilled the countless compromises which have made life for middle-class Iranians bearable.
I have Iranian friends in London who loathe the ayatollahs but have spent the last two decades living in comfortable half-exile, shopping in Paris, spending the winters in London and returning to Tehran for most of the year, where they work as doctors.
If President Ahmadinejad remains in power, continuing to thumb his nose at the West and rile the Israelis, this sense of ambiguity will surely come to an abrupt end.
The era of Ahmadinejad has become doubly intolerable for some sectors of Iranian society, now that the Great Satan is run by a guy who shares a middle name with the opposition candidate, Mir Hussein Moussavi; a man who speaks directly to the Iranian people and who tells them that Persia, a great and ancient civilisation, deserves America's respect.
Mr Obama even had the good sense to apologise for the British and American-backed coup against Prime Minister Mohammad Mossadeq in 1953 after he tried to nationalise Iranian oil.
That was the coup that ushered in the Shah and it still really upsets most Iranians, who are not die-hard supporters of the Pahlavi dynasty.
So far, Mr Obama has played a blinder.
But events have put him in a blind spot. President Ahmadinejad is desperate for him to publicly support the opposition so that he can claim America is meddling as usual.
Mr Obama has refrained from doing that. But the longer he sits on the sidelines the more he will look inert.
It is a tough call. The US president does not want to be accused of inadvertently hijacking the opposition.
Nor does he want to be remembered as the president who missed an historic opportunity.
Treading this fine line between the Great Satan and the Great Absent - is this the first big foreign policy test of Mr Obama's presidency?
Matt Frei is the presenter of
BBC World News America
which airs every weekday on BBC News, BBC World News and BBC America (for viewers outside the UK only).
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