In the country where I live, most of those who go to Syria goes to the same fundie musques often partially funded by Arabic oil money. The Imams of course treat it like it's a mystery why this is the case (it has be documented they have been involved in sending young people away for "Quran schools" which act as a halfway houses to Syria) all the while they preach the medieval interpretation of Islam and do their level best to for instance ensure the women do not get jobs but live on the dole.
Part of recognizing not all Muslims are terrorists is to recognize Muslims don't turn into terrorists because they catch a cold but there are specific environments which breed terrorists.