I don't think the US has a strong motivation to fight against this particular status quo. Politicians are aware that Americans like drugs, and they're probably very hesitant to put themselves directly between supply and demand.<p>Furthermore, I imagine a line of reasoning exists somewhere that a weak neighbor is a neighbor who can be manipulated. If we need tactical placements in that neighbors back yard, chances are that they can be exclusively acquired through threat of force and bribery (Edit: that is to say, they can be bullied, and the US is the closest and most effective bully around when you're Mexico. Keep in mind they're not just being bullied with threats, but also with promises of a more cooperative and economically entwined future).<p>Realistically, I think pretty much all Americans want to see Mexico succeed. Mexican culture is appreciated and related to here. Sadly, things being the way they are it seems difficult to be the one to actually get in the way of any of the obstacles holding Mexico back.