I flew out to the Middle East expecting to lose a crucial debate on the subject of tackling Muslim extremism. The showdown was to take place in Doha, in Qatar, home of al-Jazeera, bin Laden's television channel of choice. Worse, Doha is also home to a cleric who Britain, rightly, refused an entry visa. Yusuf al-Qaradawi is an advocate of Palestinian suicide bombings, permits female genital mutilation and supports theocracy. Rarely are these issues discussed openly in the Arab world and the concept of extremism, as precursor to terrorism, is viewed as a Western concoction.

During the 7 July suicide attacks in London, I was living in Saudi Arabia. Saudi friends refused to believe that terrorism had anything to do with the rigid, literalist, soulless brand of Islam they had developed. The fact that the lead bomber, Siddique Khan, wore a Saudi headscarf for his 'martyrdom message' and shared an extreme form of the Saudi Wahhabi theology was not sufficient proof. A 2005 Pew poll showed that nearly 60 per cent of Arabs refused to believe that 11 September was carried out by Arabs.

Even today, the ubiquitous conspiracy theories about Israelis perpetrating 11 September penetrate Arab cities' coffee houses. Friday sermonisers roar about Western imperialism and moral degeneracy, but fail to take any responsibility for the socioeconomic underdevelopment of their countries. Unable to tolerate the pernicious extremism in Saudi Arabia and other Arab countries, I gave up hope and returned home to Britain in 2005. And then I was asked by the avant-garde Qatar Foundation to return to the Middle East to debate the presence of extremism among Muslims.

In a stadium filled with young Muslims from across the world, BBC journalist Tim Sebastian probed arguments from both sides of the panel. If the Qatar Foundation truly believed in free speech, then it would listen to my criticisms of mosque sermons, Saudi universities, destruction of Muslim heritage in Mecca and Medina and suicide bombings.

Would it? Al-Jazeera and other Arab networks stoke the flames of the Arab-Israeli conflict by referring to suicide bombers as 'martyrs'; an audience exposed to such language would not take well to my comments. Still, without any censorship, I was allowed to say whatever I wanted. The audience listened in silence. And to my surprise, my opponent weighed in with further condemnations of suicide bombings.

Moez Masoud, a popular Egyptian televangelist, did what few Arab Muslim scholars do: he declared suicide bombings to be haram, scripturally forbidden. This was no ordinary feat, particularly during a week when the Palestinian death toll in Gaza was rising to more than 100 people. For a young Arab scholar to defy the mob, take politics out of religion, risk popularity and break Arab consensus takes courage.

Voices such as Masoud's are rare and precious in an Arab world committed to supporting 'Palestinian martyrs'. Even in Britain, Muslim leaders equivocate when it comes to condemning suicide bombings in Israel. And yet Masoud sat in the city that is home to al-Qaradawi and declared such acts as forbidden. Whatever the outcome of the debate, Masoud has scored a huge moral victory. With young preachers such as Masoud on the rise, there is every chance of hope in the Arab world.

My side of the debate was faced by the usual Arab apathy: the West had created extremism. I was resigned to losing the motion. And then came another shock. The 400-strong audience, with Muslims from as far afield as America and India, turned to their electronic devices to carry or lose the motion: 'This house believes Muslims are failing to combat extremism.' We waited. No people wants to admit to collective failure. And yet the audience carried the motion with a massive 70.4 per cent in favour: Muslims are failing to combat extremism.

I was in store for another shock.

When I lived in Saudi Arabia, the one aspect of Saudi intolerance that irked me most was their refusal to allow people of other faiths to worship freely. There was no church for the millions of Christians in a country that is considered the West's closest ally. And yet Saudi Arabia remains free to inject millions of dollars into mosques across Europe. To date, there is no single Saudi cleric who has openly supported the cause of the largest religious minority to worship freely. Nor will the British or American governments request these basic rights for their citizens, lest they upset the House of Saud.

I met a professor of Islamic studies from Qatar University. Dr Abdul Hameed al-Ansary, without my prodding, reiterated his public position of support for churches in Qatar. Meeting an Arab Muslim scholar from a conservative Gulf state who proudly tells me that Qatar's first church building is nearly complete gives me a sense of hope that soon Saudi Arabia may follow where its neighbours lead. There are churches in Kuwait, Dubai and ancient Christian prayer halls in Yemen. The Arabian peninsula now has churches as Europe has mosques.

Meanwhile, the extreme, vacuous misinterpretation of Islam that focuses on rituals and rigidity is alive and well in Britain. Recently, I was at a sermon at Imperial College, London, where a young, radical preacher fired off a sermon about excommunicating Muslims, or takfir. It is out of such rhetoric that the jihadist mindset is born, taken from an ahistorical reading of scripture. When this is married to political grievances, pioneered by Islamist movements, we have suicide bombers.

Those who share my religion in Britain are yet to follow Qatar and publicly admit to an extremism problem in our communities. For as long as radical sermons go unchallenged, and Islamist groups adopt doublespeak in public discourse, condemning terrorism while disseminating extremist literature, British Muslim activists will be in the grip of extremism.

The older generation of immigrant Muslim leaders must move aside and give way to younger British voices. Then perhaps we, like those in Doha, can admit that social and political extremism is rife in Muslim communal discourse.

· Ed Husain, author of The Islamist, is deputy director of the Quilliam Foundation. The Doha debates will be broadcast on BBC World today at 8.10pm