As this Register editorial points out, Hillary is to be commended for a bit of honesty in noting that the U.S. bears some responsibility for the violence in Mexico these days. But half-right seems to be as close as she can get. The notion that we can quell the violence by sending more money to the Mexican government, inspecting more vehicles crossing the border, and raiding some gun shops in the Southwest is beyond ludicrous. What conspicuous enforcement most often does is to weed out the weak sisters in the drug trade, further entrenching or bringing to the fore those most adept at violence, ruthlessness, concealment.
Here's another expression of a similar point of view, and a piece written a few weeks ago by my Register colleague Steve Greenhut and one by me (note that we were several weeks ahead of the mainstream media in calling attention to this situation, and almost unique in offering a solution that might work rather than doubling-down on failed policies). And here's a link to the piece in Foreign Policy magazine alluded to in the editorial.