Every year, I pay the US government protection money at a higher rate than the mob demanded (~35% vs ~15%). They mark their territory, control who enters and exits, and demand compliance with their rules. If you are under their protection, they give you a little document that tells other gangs not to screw with you.
They back all of this up with guns and threats of violence, held by unelected thugs. They give you a process to prove your innocence, but the process itself is a punishment, since it is a huge resource drain to go through.
The FBI are the most visible thugs.