Terrorists are often middle-class and well-educated

In Muslims in India 'Targeted With Suspicion' by Pamela Constable writes,

...in the wake of the devastating July 11 train bombings in Bombay, in which more than 200 people were killed, residents here say they feel fingers of suspicion and hate pointing at all Muslims, not just jobless slum youths and bearded students from Islamic radical groups.

By why should it be confined to them? In fact, the recent British terrorists

...include middle-class, well-educated young men born in Britain. At least one of them converted to Islam only recently. ...among those arrested were the white son of a former Conservative Party worker, the son of an architect and an accountant and a heavily pregnant woman. Some had studied at university and came from families that owned several properties or ran their own businesses.

They don't sound like the stereotypes the article is presenting. And Marc Sageman is cited as saying,

Al Qaeda’s members are not the Palestinian fourteen-year- olds we see on the news, but join the jihad at the average age of 26. Three-quarters were professionals or semi- professionals. They are engineers, architects, and civil engineers, mostly scientists.