The war on drugs has been an abysmal failure economically and socially. It has cost billions of dollars, and done nothing but overburden our judiciary system, clog our jails, and create an atmosphere of violence stemming from the increase in the street value of substances deemed illegal by our short-sighted legal system.
It has failed to curtail the use of illegal drugs, and has created numerous foreign entanglements, where our military is being used to fight drug cartels,which radically increases the street value of the drugs.
Ending this failed policy will decrease the value of the substances and will result in a large decrease in the violence associated with the drug trade.
Simply put, end the value of the illicit drugs, and you end the motive to protect the illicit profit.