How do I know that the 'War on Drugs' was a complete fraud; perpetrated on the American public?

Three letters: C, I, and A.

https://consortiumnews.com/2015/09/10/cia-and-the-drug-business/

A very small snippet from a very lengthy and informative article -

Federal drug law enforcement’s relationship with the espionage establishment matured with the creation of CIA’s predecessor organization, the Office of Strategic Services. Prior to the Second World War, the Federal Bureau of Narcotics was the government agency most adept at conducting covert operations at home and abroad. As a result, OSS chief William Donovan asked Anslinger to provide seasoned FBN agents to help organize the OSS and train its agents to work undercover, avoid security forces in hostile nations, manage agent networks, and engage in sabotage and subversion.

The relationship expanded during the war, when FBN executives and agents worked with OSS scientists in domestic “truth drug” experiments involving marijuana. The “extralegal” nature of the relationship continued after the war: when the CIA decided to test LSD on unsuspecting American citizens, FBN agents were chosen to operate the safehouses where the experiments were conducted.