Why are Arabs the bad guys? Stereotypes?

I was wondering, why are Arabs both in novels and in films the bad, scary guys all the time? From what I've seen, Arabs are personified in every work as complicated and conflictive people. Like Meursault said, "The day of my arrest I was first put in a room where there were already several other prisoners, most of them Arabs", (Camus, pg. 72). And concidentially, he has shot four times and Arab.

My opinion about all this is that the Arab society and most of all, their religion, is based on a strong commitment to their God. So, these people feel they owe their creator something, and as they are 'called' by Him, they sacrifice in honor. It's somehow related to today's world; terrorists since 2001 and before, have been attacking and attempting to places like New York City and London. This is a result of an inner conflict with this countries themselves, but all the attempts can be said are suicidal. But why suicidal? These cultures show their strong beliefs by offering themselves; killing themselves and harming others.

I can also relate the Arab reality in films and novels to our reality here in Colombia. Colombia has been a country known for the 'wonderful' marihuana and cocaine, all around the world. It's not our fault countries who blame that we're a bad place continue to buy drugs and at the same time be the ones that create a harsh image about us. We wouldn't be how we are if there weren't any big powers who supported us with THAT kind of business. So, my point is, we also appear everytime a gringo in a movie says marihuana or cocaine, it's the same old comment: "The best weed is from Colombia!" Or if they want to refer to illegal businesses, or terrorists, or assasins COLOMBIA is the word (or Arabs). I know and I can face the fact this conflicts are present, but some people could help end them instead of highlighting each one.
Can we base ourselves on a stereotype?