Use landmines on the southern border

This would deter invaders from crossing the border through anywhere that is not an official entry location. The US military indusrial complex isnt going to go away overnight so we could use landmines on the southern border to get them to spend money on something useful to united states citizens. We could use this area denial technique that militaries use when they do not have enough soldiers to prevent an opposing force from moving through a specific area. Im sure with just one of the billions of dollars sent overseas you could create the signs every 100 yards to warn invaders to not cross the border and heavily mine areas where the fence is not able to be utilized.