Who Actually Wants Cannabis Prohibition To Continue? 
One of the principal lessons in the Art of War is to ‘know thy enemy.’ Therefore, it behooves cannabis law reformers to understand what small, but powerful factions in American society actively work to maintain the status quo of Cannabis Prohibition:

1. Law enforcement – There is no greater strident voice against ending Cannabis Prohibition than from the law enforcement community—from local sheriffs’ departments, to the Fraternal Order of Police, to state police departments, to federal law enforcement agencies.
2. Federal and state bureaucracies born from cannabis Prohibition itself – Washington, D.C. and most state capitals have created dozens of anti-cannabis government agencies to both maintain and enforce existing cannabis Prohibition laws. Examples: Drug Enforcement Administration, Office of National Drug Control Policy (a.k.a., drug czar’s office), DARE, Partnership for a Drug-Free America, National Institute on Drug Abuse, Substance Abuse Mental Health Services Administration, National Drug Control Information Center, et cetera.
3. Alcohol, tobacco, and pharmaceutical companies –
   Historically, alcohol, tobacco, and pharmaceuticals companies play both ends against the middle when opposing cannabis law reforms for the simple reason that all of these industries will lose a portion of their market share to legal cannabis.
4. Private corporations that prosper from cannabis Prohibition – Numerous private companies donate significant funding annually to anti-cannabis politicians and organizations to maintain the status quo. Examples of such are private prisons, drug testing companies, rehabilitation services, communication companies, contraband detection devices, interdiction services, and high-tech companies. +

— ENDING CANNABIS PROHIBITION IN AMERICA | Cato Unbound (NORML executive director Allen St. Pierre on the movement to end cannabis prohibition in the U.S.)