The US's fault?

According to Hillary Clinton the US is to blame for much of Mexico's violence?

http://www.reuters.com/article/vcCandidateFeed1/idUSN25429486

Is she right? Probably so, if the US could control its demand for drugs then probably Mexican druglord would not have the power they do. Moreover, drugs being a black (i.e. illegal) market present a great price markup from the marginal cost of producing them. If they were made legal then they could be regulated and drug lord would lose their monopolic power.

Maybe drug legalization should become an issue in both Mexican and US political agendas...