Perhaps they should take a look at what a great job the UN peace keepers did on Rwanda, then reconsider the request.
IDK dude. The Mexican government needs help from someone. Maybe not the UN, but someone. And letting them fall into depravity only endangers our country even more. Even if we were to clamp down on the border (doubtful given our politically correct politicians), having an unstable neighbor is just fundamentally unsound policy that, in the future, may very well jeopardize our own security.
IDK what the answer is. I'm sure we'll be accused of meddling if we try to directly intervene or something, but the government definitely needs help.