Every regime has its own name for its secret police. Mussolini's OVRA carried out phone surveillance on government officials. Stalin's NKVD carried out large-scale purges, terror, and depopulation. Hitler's Gestapo went door-to-door ferreting out dissidents and other political "enemies" of the state. And in the U.S., it's the Federal Bureau of Investigation that does the dirty work of ensuring compliance, keeping tabs on potential dissidents, and punishing those who dare to challenge the status quo.
Whether the FBI is planting undercover agents in churches, synagogues, and mosques, is issuing fake emergency letters to gain access to Americans' phone records, is using intimidation tactics to silence Americans who are critical of the government, or is persuading impressionable individuals to plot acts of terror and then entrapping them, the overall impression of the nation's secret police force is that of a well-dressed thug, flexing its muscles and doing the boss' dirty work.
It's a far cry from the glamorized G-men depicted in Hollywood film noirs and spy thrillers. The government's henchmen have become the embodiment of how power, once acquired, can be so easily corrupted and abused.