Anti-Mexico? Anti-Mexican? Thanks for at least being honest about your motivation.
As far as the actual protection of the US borders where terrorism is concerned - I'll put more stock in those folks who recognize that the border with Mexico only makes up about 1/8 of the total US border and coastline.
You have to understand what is happening in Mexico, however. The government of el Presidente Fox is playing footsies big-time with our other enemies: Iran, Russia, Cuba, Venezuela, etc. etc.. Those nations want a foothold in this hemisphere and that, of course, has nothing to do with the ridiculous NAFTA treaty.