From Wikipedia “It is estimated by the Pentagon and company representatives that there are 20,000 to 30,000 armed security contractors working in Iraq, and some estimates are as much as 100,000, though no official figures exist.” The majority are Blackwater. They go totally unchecked and up until this point not even one has been prosecuted for anything. There have been countless “problems” with them, but the chimp can’t afford to lose them or we’d have to send in troops we don’t have.
Here’s 2 good videos about Blackwater:
This one lays things out pretty well (oops, just noticed you posted this one) http://youtube.com/watch?v=yJUEULWEP9c
This one is just straight up disturbing http://youtube.com/watch?v=xMdHKOUm7NM