I submit to you that perhaps the problem with the War on Drugs is that it is not a real war.
If you made taking drugs and selling drugs a treasonous offense (as helping the drug trade enriches our enemies) and mandated the death penalty for anyone who sold drugs, and a 1 shot and you are out deal for anyone taking them (the first time you are caught you get life in prison...the second time death), do you really think that the drug trade would continue in America?
If you cooperated with the Mexicans (and other Latin American countries) to send in military forces and torch any opium fields, wipe out meth labs, and kill everyone involved and everyone aiding them (inside the US, and where possible outside), would that not nearly completely stop illegal drug use?
Maybe we just have not been taking a hard enough line...