I think most wouldn't care -- a whole lot of the border is way out in the desert where no Americans are --- the parts of the border in town are already fenced -- no one minds the fences at all --- in fact if you told the people living along the immediate border that the fences were coming down --- you'd hear the biggest outcry and protests --- and those would be all hispanics. Silvestre Reyes actually became very popular among hispanics with Operation Blockade and Operation Hold-the-Line --- which drastically lowered much of the crime rate in the border towns.
Militarization will mean numerous Mexican kills and casualties. A whole lot of people will care.