The CIA is America’s analog to ancient Rome’s Pretorian Guard. The Pretorian Guard stated as a protective force, but quickly devolved into a mob interested only in its own preservation. Without any checks against its power, the Pretorian Guard extorted money from the Emperor, assassinating emperors who dared cross it, and ultimately controlled who would be emperor.
The CIA is much the same. Operating without oversight. Assassinating people who get in its way. Drug running. Corruption. Covering up its own criminal behavior (60 years later and the papers on the JFK assassination are still not public. Wonder why.)