The gentleman from Vermont might not have been entirely out of line today when he explained walls are "last century's technology". So use drones across the ~1800 miles of needed border. Specifically, an array of response drones could be enormously beneficial to CBP, ICE, and DHS in general. Drones can be programmed to automatically recharge on environmentally sound seismic pylons (detection of underground digging) that are outfitted with solar panels. Land acquisition will not be a factor in building this "virtual wall". Areas of land where building a traditional wall was not realistic or possible will no longer be the case. This will not take jobs from CBP, but instead will enhance their ability to apprehend individuals. When a suspect is identified by the drone swarm, one drone will break off and follow the suspect - simultaneously reporting their up-to-date location to CBP.
Furthermore, the United States can repurpose an array of drones in the event of a natural disaster as part of damage assessment and emergency response. 3,600 high-tech pylons and 90,000 drones should be what the President is collecting prototypes for - not blocks of concrete that will cost 18 times as much.