Did it ever occur to you that explosives may have been in that car at one time and transferred to someone else??
Did it occur to you that they were let go so they could be followed to their contacts??
This is just as plausible as your concern for these poor american/muslim idiots who would make a joke of our country.
They are going to make very compassionate doctors. You should look them up if you are ever in need of really good medical care from jokesters.