At the core of anarcho capitalist thought, is an emphasis on self-ownership and the non-aggression principle. Under the latter, individuals are free to go about their lives provided that they do not violate other people’s rights. That means people’s persons or property would be secured from external aggression.
This logic doesn’t just apply to interactions between individuals but also between society and the state.
Americans say marijuana is banned to help the alcohol industry, but maybe the real reason weed is banned is to boost the private prison industry.