Never did understand the enthusiasm for a "virtual" (aka electronic burglar alarm) fence on the border. A real chain link fence has real deterrent value and doesn't suffer from power outages, software crashes, broken wires, and all the other ills of electronic devices. It's also cheaper.
By the way, it doesn't take much of a truck to push thru a chain link fence, so they don't keep out vehicles. A vehicle proof wall like the Israeli's put up is much more expensive than a fence.