I didn't read the linked article--it certainly seems to frame the issue as rationalists vs. barbarians, not humanity vs. the environment (and the flaws of humanity), so thanks for pointing that out.

I do think fundamentalists/extremists/terrorists have an asymmetrical advantage in the short term in that it's always easier to cause damage/disorder than improvement/order. This quote above seems to be a particular example of this phenomenon.

However, I have to agree with Jiro's comment. Extremists may be able to destroy things and kill people, but I wouldn't say they've been able to conquer anything. To me, "conquer" implies taking control of a country, making its economy work for you, dominating the native population, building a palace, etc. Modern extremists commit suicide and then their mastermind hides silently for a decade until helicopters fly in and soldiers kill him.