That has always been his stance consistently while dismissing and downplaying the role of the West that fuel the conditions that give rise to the insurgent group and anyone that begs to differ with him, he calls them "regressive leftist" or "Pro Islamist leftist.
Cato I have seen his interview with The Young Turks and he is clearly saying that Islam was not solely responsible for the rise of Islamism. He says it is the main factor, but not solely responsible for this. Now, I don't know if said this sometime in the past, because I don't know everything the man says/said, but if he said, he is stupid, no doubt about this.
I find it myopic to blame Islam as the main contributor of the mess in the Middle East. I would rather say Islamism is a symptom of the problem.we didn't have the likes of Al-qaeda before until 80s when US supported mujahiddeens in Afghanistan hence the emergence of Taliban and then Al-Qaeda which emerge as a reactionary insurgents due to US intervention in Middle East. Hamas too emerged in the late 80s as a result of Israel oppression against Palestine.
Shia-Sunni split became worse after US topple Saddam and impose Maliki(Shia) who uses his power to marginalize Sunnis.
As for KSA, we all know it was a created as nation state with the help of the British empire to undermine Ottoman Empire's control of ME, we all know how US became an important ally of Saudi and how they(KSA) got petrodollars to spread their cancerous divisive ideology that supports literalism to the core known as Wahhabism around the Muslim World.
Considering all that I don't see how "Islam" is the main contributor to the mess in ME and I don't see why Chomsky need to do that just to appease secular liberals. If we look at the history Islamism was a reactionary force against the dominance of the British Empire and West that imposed Kings and later on. Secular dictators on them. Not to mention how Iran wanted to practice secular democracy until CIA funded the coup that overthrew Mossadegh and impose a monarch hence the Islamic revolution.
So yes a lot of blame has to go to Western imperialism than just Islamism.
Well let's start with Wahhabism and KSA. First, Wahhabism was there before British and before USA. It's an Islamic product, we all know this, it is as old as Islam itself. As you said, they apply Islam with brutal literalism, so if Wahhabism is so bad it is Islam's fault. It is in its scripture. And why is this approach wrong?
The Saudi have beaten the Rashidis without the help of the British before and only Ottomans saved them. It is not like without the help of British they wouldn't have beat the Rashidis again and the support of British was in arms and in money, not in men. The British just happened to ally with all Ottomans foes(Saudi being only one of them), but they didn't provide men. You can hardly blame British for this, for Brits they were some bedouins who happened to be Ottomans foes, they had no idea what Wahhabism is. The most important thing that helped Saudis to gain control of the all today Kingdom was the wahhabis, their support and alliance was crucial. You cannot deny this.
It is not USA fault, that there's a lot of oil there. If USA wouldn't have allied with them it would have mattered? Not to much, if any, it is the fact that they have oil, that helped them maintain in power, have their own army, have the money to spread their poison and to buy weapons. If not USA, Russia or any other power would have gladly fill the vacuum, I think we can agree with this. It is disingenuous to blame the West for Saudi having money and will to spread their Wahhabism and that they are in power. Oil is a necessary resource and unfortunately it happens to be there.
About Iran, yes USA is clearly guilty for Iran not becoming a democracy back then(Shah was secular as well), but you cannot blame them for supporting extremists to get in power there, although it is true that maybe without this, Iran could have been a democracy now. Could have been... Because you can never know with Islam, as Islam and democracy doesn't fit to well together, and in the end the most powerful ideology wins and Islam is eating democracy at breakfast...
Shia-Sunni split would have become worse as well if Arab spring would have removed Saddam Hussein. Idiot Bush was just a trigger as Arab Spring was for Libya, Egypt, Syria, Bahrain . In the end whatever thing would have removed Saddam Hussein the same shit would have come from that place. You surely wouldn't expect a Sunni to peacefully get prime minister in a Shia majority country. The place was already sectarian when the secular dictator was there. It is bad when they are installed there, it is bad when they are removed as well. In hindsight it appears secular dictators are not a bad idea for that part of the world.
Mujahideens, Al-Qaeda, ISIS, Muslims Brotherhood, all of them are Islam products. Without Islam you don't have any of these.
Colonialism/Imperialism/USA waging war in the Islamic word. Islam loves to play the victim card, to find excuses, everything but blame itself for all the mess in majority muslim countries and and for the misery of muslims everywhere in the world. We have Ottoman empire colonialism over Balkans, you don't see Bulgarians, Greeks lay guilt at them, you have British, French colonialism in India and non muslim Indochina, no crying there, you had NATO in Serbia but you don't see terrorist attacks from the Serbs, Armenians and Germans expelled from their lands, even genocide and they don't have terrorists.
Every bad thing that has happened to Islam, has happened in other parts of the World as well Cato, but in Islam it is blown out of proportion. Mainly to excuse Islam. I mean you really have to wonder if you are not very ignorant or very naive, or both together to think that this is just an accident.
Getting back to Mr. Chomsky, is there anywhere something, where he says that Islam has a contribution in all this mess, even a minimal one. Because if he wants to be be considered an honest broker in this debate, that he likes to be part of, he just has to put Islam there as well.