...;no we install them along our highways to hide trees and other natural sound barriers .......must be 20,000 miles of concrete barries in the US by now,not at the border
I'm sure you're right. Those in and around Atlanta are supposed to be acoustic barriers to cut down the noise from the interstates.
The Israeli wall extends 30 feet below grade to inhibit tunneling. We would need at least that to cut down on the "commerce" moving underground.