I don't desire to do a full reply at the moment, Kunarian, but I do wonder if you've looked at some of the things regarding law enforcement in the U.S., as well as private military organizations.
First, we have privatized security forces of one sort or another all over the place. Second, many, many of our prisons are actually privately run. For example, Corrections Corporation of America alone has responsibility for at least 70k inmates. Third, I don't know if you've noticed, but America is HUGE on private military contractors. Also known as, essentially, corporate soldiers. Blackwater, or whatever it is now, announced not too long ago that they could field as much as a brigade - that is, an average of around 4000 troops. And if you think that American megacorporations aren't willing to use force, or to hire contractors/build their own, then you really do need to research some of them.
Oh, and yes, if it is truly a megacorporation, it probably lives in America, or at least has a second home here.