It's not a cop out. There are many parties which share blame: the Public for its fearful ignorance and fear, the prisons for profiteering and massive media and lobbying influence, law enforcement for enforcing the "lex malla" of drug policy with violence, various government organizations of various nationalities (including to a large degree the US) for using hard drugs as a tool to manipulate political, social, and economic situations, assassinations, cartels and gangs that sell drugs to fund human trafficking and murder, the list goes on…
There's a lot of blame to go around. The prisons share a whole lot of it.