Why do Atheists defend Islam?

[abaris]

I'm pretty sure this was the Golden Age you refer to, so how in particular do you see Islam as "an accelerant to progress" then, or at any time? How do we know Islam had anything to do with any social or intellectual progress for those who happened to be Muslim? Where does the Koran encourage forward-thinking intellectualism and social egalitarianism (well, sorry, guess the latter is a non-starter)?

Wrong question. Islam did neither encourage nor prevent progress. For one simple reason. It never had an ultimate religious authority, but many different people interpreting and preaching their understanding of the Quran. So it always was up to the leaders how liberal or backwards their regions and territories were. And, as has been said, the Quran is as ambiguous as the bible and open to interpretation.

Compare that to Western society, where the pope and foremost the monasteries were the only ones preserving knowledge, but never building on it. The pope and through him the church, were the ultimate authority in all spiritual and educational matters.

I say Western, because Byzanz didn't fall under that rule. And accordingly it was also more advanced than the West.

The decline of liberal Islam is due to many factors over the centuries. The power struggle within the Islamic world, which led to the rise of less educated nomadic people to power and probably most importantly, the Osmanic rulers taking over the largest part of the Middle East. Which prevented independent development.