1. Drug Cartels: If drugs are legalized, then various drug cartels in Mexico, United States, Italy.etc will become obsolete.
2. Banking Cartels: Without the drug money, the banks such as HSBC and Goldman Sucks will lose a major part of their revenues.
3. Pharma Cartels: If soft drugs such as marijuana are legalized, then the expensive painkillers marketed by the pharma giants will lose their market share.
I agree with 1) and 3), but I'm not sure about 2).
In my opinion drug users should be decriminalized for a very simple reason: They only do harm to themselves. I think as far nobody else is harmed people should be free to do whatever they want with their bodies and souls. Decriminalization will also free police resources for more important tasks.
Criminalization of drugs only drives prices up and quality down which leads to more drug-related crime and higher health risks.
ya.ya.yo!