It can be gotten 90% rid of. Nothing is perfect. You start with 15,000 mobile troops on the Mexican border
I am assuming it also applies to the Chinese and Irish who also are coming in.
You betcha !!
Special training? Could Border Patrol do this? Shoot to kill, arrest and repatriate, or stand around and look fierce? Armed with what weapons?
Lots of things to think about with your suggestion.
Also, what about the coastlines?