Religious extremism, and in fact extremists of all kinds, always exist everywhere. What the USA has done has been to topple organized states or regimes that were able to keep some order and rule of the law in their territories, fuel hatred and desperation by killing hundreds of thousands of people, bombing the cities and destroying any form of economy, also with the aid of a decade long and ferocious embargo (the estimates put to a million the victims of the embargo, mostly children), and finally providing weapons and training to "rebels" to produce internal revolts to weaken the "enemies". A myopic and downright evil strategy that is now fully showing its obvious results.
