Iranian exiles in the United States have played an important role in supporting the recent protests in Tehran - but their role is coming under increasing scrutiny.
A nondescript industrial estate in the San Fernando Valley on the outskirts of Los Angeles may be an unlikely place to start another Iranian revolution.
Arrests have not stopped the rallies in Iran
But Woodland Hills, California, is the headquarters of the satellite television station National Iranian TV (NITV) whose programmes are beamed into Tehran and other parts of Iran to illegal satellite dishes in private homes.
It is one of half a dozen satellite stations set up by Iranian exiles in the United States.
NITV is run by Zia Ataby, a former pop star who moved to Los Angeles in the 1980s.
It says it aims to promote "equality between men and women, separation of religion from government, human rights, freedom of speech and the media, and democracy" in Iran and is not affiliated with any political party.
Its combination of light entertainment, talk shows and politics has proved explosive in Iran.
NITV for the Iranian Government is more dangerous than America or other countries and that is why they have tried anything to cut our voice
This week former Iranian President Ali Akbar Rafsanjani warned Iranians "not to be trapped by the evil television stations that America has established".
And some outside observers believe that the exile community and its stations are playing a key role in the student protests that are sweeping the country.
On Wednesday President George W Bush expressed his support for the protesters, calling them "courageous souls who speak out for freedom", adding: "America stands squarely by their side."
Stirring up trouble?
Al Santoli of the Washington-based American Foreign Policy Council says that the foreign broadcasts - and the internet - are playing a similar role to programmes beamed to Eastern Europe just before the end of the Cold War.
"The protests are being driven by young people who have enough exposure to the outside world to know there is something different" from the repressive Iranian regime, he told the BBC.
I am not surprised that students and others in Tehran responded to the call
Iranian lecturer in US
"It is very important that people know that there are others who share their protests, especially when the official media are censored," he added.
Mr Ataby told Reuters news agency: "NITV for the Iranian Government is more dangerous than America or other countries and that is why they have tried anything to cut our voice."
He says his eight telephone lines and four fax lines are continually besieged by comments from viewers in Iran.
"I am not surprised that students and others in Tehran responded to the call," said Majid Mosleh, an Iranian who teaches political science at College of the Canyons in Los Angeles.
And reports from Iran suggest that the regime is moving to block access to Western internet sites for the estimated three million Iranians with access to the web.
Meanwhile, radio stations like KSRI, also Los Angeles-based, are circulating petitions calling for the Iranian regime to be replaced by a democratic and secular one.
Would US aid help?
US neo-conservatives would like to provide direct aid to the exile radio and TV stations, which are mainly funded by donations from wealthy exiles.
Republican Senator Sam Brownback - who was also a strong supporter of Iraqi exile leader Ahmed Chalabi - has proposed that the US Congress provide $50m to fund Iranian exile groups and stations.
To imply there is going to be a US intervention, or depict the regime as being weak, may give false hopes to these idealistic young students
Professor Richard Dekmejian
But others warn that too close an identification with the United States could be counter-productive for the Iranian opposition movement.
"It's very important at this critical juncture that the opposition should be seen as independent of the United States, especially after the Iraq war," said Mr Santoli.
Otherwise the hardliners would have the excuse they needed for a crackdown, he added.
And others warned of the talk shows fuelling unrealistic expectations among the protesters.
"To imply there is going to be a US intervention, or depict the regime as being weak, may give false hopes to these idealistic young students," said Richard Dekmejian, professor of political science at the University of Southern California.
But their influence may be growing within the US among right-wing policy-makers.
Political exiles have often played an important role in US politics - not just in Eastern Europe, but also in regard to Cuba where an active exile community in Miami has gained a dominant role in US foreign policy towards the island.
The Iranian exiles may be no more than enthusiastic cheerleaders for democracy, but one way or another they may yet end up playing a key role in the unfolding events in Tehran.