Why Won't Muslims Denounce Their 'Extremists'?

In the wake of the recent London bombings, a number of writers around the web are re-asking the very good question “Why don’t Islamics denounce and suppress their own so-called ‘extremists’ more effectively?”
In his aptly titled blog entry “Is it Islamic “extremism” — or is it Islam itself?” Objectivist writer Robert Bidinotto begins:

In the wake of the London bombings, we are forced again to confront this most uncomfortable question:
Do the Islamic fundamentalist terrorists truly represent a marginal minority among Muslims worldwide?
Or is the term “Islamic fundamentalist” really just a redundancy?
I am by no means an expert on Islam. But since 9/11, and countless terrorist incidents since, I have been patiently awaiting evidence that the majority of Muslims worldwide repudiate the premises and tactics of Islamic terrorists.
Well, I’m still waiting. And there comes a time when one must finally draw conclusions, however painful, from the facts presented.
If there really is some sort of ongoing war between “extremists” and “moderates” for the soul of Islam, it appears to be one of the quietest contests in the history of ideological warfare.

Instapundit addressed this topic yesterday as well, and provides this quote from an article by Tom Friedman in the NYTimes:

Because there is no obvious target to retaliate against, and because there are not enough police to police every opening in an open society, either the Muslim world begins to really restrain, inhibit and denounce its own extremists – if it turns out that they are behind the London bombings – or the West is going to do it for them. And the West will do it in a rough, crude way – by simply shutting them out, denying them visas and making every Muslim in its midst guilty until proven innocent.
And because I think that would be a disaster, it is essential that the Muslim world wake up to the fact that it has a jihadist death cult in its midst. If it does not fight that death cult, that cancer, within its own body politic, it is going to infect Muslim-Western relations everywhere. Only the Muslim world can root out that death cult. It takes a village. . . .
The Muslim village has been derelict in condemning the madness of jihadist attacks. When Salman Rushdie wrote a controversial novel involving the prophet Muhammad, he was sentenced to death by the leader of Iran. To this day – to this day – no major Muslim cleric or religious body has ever issued a fatwa condemning Osama bin Laden.

See Instapundit’s full discussion for more analysis and a link to information about one Muslim group that has, in fact, issued a Fatwah against Osama bin Laden.