Although surveys show that most followers of Islam in the U.S. reject extremist views, many voices of moderation aren't being heard. And some terror experts say groups that sound moderate often have a hidden, radical agenda.

The Council on American-Islamic Relations (CAIR), which bills itself as the largest Muslim civil rights organization in the U.S., has won both praise and criticism.

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CAIR has long maintained that it is a moderate force that soundly rejects terrorism. "CAIR's position on terrorism is very clear: We have condemned it persistently and consistently wherever they do it, whenever they do it," said Corey Saylor, governmental affairs director at CAIR.

Yet some critics note that former CAIR associates have been convicted on terrorism-related charges and express alarm that the group was named an unindicted co-conspirator in a terror-related trial. CAIR officials were linked to the Holyland Foundation, a major Islamic charity that allegedly funneled money to Hamas.

When asked to specifically condemn Hamas and Hezbollah — two groups that have been identified by the State Department as terror organizations — CAIR refused to directly condemn them.

CAIR called accusations against it "guilt by association," and said they were not accurate depictions of the group's activity.

"This organization stands on its record of moderate interaction with government and law enforcement and other civil groups," Saylor said. CAIR helps Muslims "contribute more to the overall goals of this society which is multiracial, multiethnic and multireligious," he said.

Yet some Muslim critics charge that CAIR is not a voice of moderation.

"The culture of CAIR is the same as Usama bin Laden, but they have two faces," said Ahmed Mansour, director of the International Quranic Center, an organization committed to democracy and reform in the Muslim world.

"Who are the moderates?" said Mansour, an Egyptian-born scholar. "You probably never heard of them, and that, they say, is part of the problem. The message of peace does not make the news."

Yet more voices of Muslim moderation are emerging in the U.S. In the aftermath of 9/11, Iraqi refugee Zainab Al-Suwaij created the American Islamic Congress, a non-profit organization that promotes tolerance and interfaith dialogue.

"We have a campaign, for example, called 'No Buts,'" she said. "We do not accept any excuses for radicalism and extremism and terrorism."

The Free Muslim Coalition offers another moderate voice in Islam struggling to be heard.

"We believe the true Muslim perspective was not being represented, the people who so called represented us, represented a very small ideology in the Muslim community," said Kamal Nawash, the group's president and founder.

Terrorism experts say the growing chorus of moderate Muslims must be encouraged and supported by U.S. officials. As some analysts predict, the fate of the Western world depends on whether moderates can wrest away the center of gravity from Islamic radicals.

David Lee Miller currently serves as a New York-based correspondent for FOX News Channel (FNC). He joined FNC in 1996 as a London-based correspondent.