“The virtual wall doesn’t work.”
No kidding. Having all the sensors in the world doesn’t help much if the the people manning them get orders to ignore what they see, or shut them off.
I’ve always been VERY SUSPICIOUS of that concept, and I am still that way. We need to show them a BARRIER that they will have to deal with.
We will need both. And as Israel learned the hard way, they will build (I am sure sure they already have some) tunnels under the wall so we will need to detect underground activity