Unfortunatly.. I think it's going to take... a Minuteman getting shot by the Mexican Army before anything will happen...
Then.. all hell will probably break loose...
There is a lot of "pent up" public sentiment to get tough with Mexico over this kind of crap..
But, on the other hand.. I can see where getting tough will force the mexican lower class into the arms of left wing radicals.. resulting in someone like Bolivia's pro drug Evo Morales or Venezuela's Chávez..
Personally.. I think it has to happen.. sure we'll end up with an vocal, left wing, anti-American Mexico.. but we can at least go to war against that.. what we have now is an impossible situation to deal with..