How to tell a terrorist from a criminal

In a lot of places, including here and in Colombia, the "insurgents" terrorize people, kidnap, bomb enemies, are involved in drugs, and of course kill politicians and police. But the criminal gangs in the US and Mexico do a lot of these things too.

But how can you tell which is which?

From StartegyPage:

Thugs Just Want To Have Fun

....Al Qaeda wants to establish a global Moslem caliphate, which has ideological, social, and political implications of a very high order. The Zetas want babes and billions in the bank, they don’t care if you worship Zeus or Dr. Seuss, just don’t cross the gang.