De-criminalizing them, then subsequently letting small companies pop up to manufacture them in very controlled areas, then thirdly regulating them, would cause the price to drop considerably. Drug mules would cease to exist, prostitution would drop a bit, south American (as well as middle eastern) cartels would completely pull out of the drug trade in the US, and mobs would no longer have that area to abuse.
"War" is a misused term.
You forgot to add in all the increased tax and licensing revenue.