U.S. policy on drug trafficking is not consistent with the need to put an end and actively repress the consumption of drugs. The solution is not based on the destruction of a native plant, coca, in the continent, but on an active fight against the Colombian drug mafia, which has created a great money and crime empire in Colombia with powerful ramifications outside its borders.
The solution is based on the destruction of coca. 
( z1 base :ARG1 ( z2 solve ) :ARG2 ( z3 destroy :ARG1 ( z4 coca ) ) )