Finish the real wall, then do the "electronic wall" with Jstars, Predator and other UAV support and Ground Surveillance Radar.

Give the "weapons free" order for border guards when armed encroachers are spotted. (Not all illegal border-crossers are huddled masses yearning to be free).

Increase the number of border patrol agents to the size adequate to get the job done. Implement a heavy weapons section of the border patrol to take on drug runners.

Institute seismic sensors along the border to detect tunneling activity.