Radical Muslim cleric Abu Hamza (search), kicked out of his London mosque more than a year ago, continues his sermons from the sidewalk — sermons that mock the Sept. 11 and Madrid attacks, praise suicide bombers and call on young Muslims to lay down their lives for jihad.

It's a call to arms that the British government would rather not be hearing but is powerless to stop. Hamza is the first imam to have his citizenship revoked under new anti-terror laws, but he's been fighting his expulsion with the help of taxpayer-funded lawyers — and winning.

Most Muslims in the United Kingdom call him a crackpot, but others like shoe bomber Richard Reid (search) and the 20th hijacker Zacarias Moussaoui (search) took his message to heart.

Inayat Bunglawala of the Muslim Council of Britain (search) said that the majority of Muslims can't abide by Hamza's teachings, and he's not welcome at any of the more than 1,000 mosques in Britain.

The U.K. isn't alone in facing such sedition from within. Other European countries are also dealing with the fact that some vehemently anti-Western clerics are spouting similar messages in mosques from Manchester to Madrid.

And those other nations are joining the U.K. in trying to do something about the problem. Denmark and Holland are seeking to limit the influx of religious leaders, and France is trying to deport an Algerian imam who advocates domestic violence, but is running into legal obstacles.

Click here to watch a report by Fox News Channel's Amy Kellogg.