The amazing thing about those who want the borders to remain open is that they are the same ones who see no problem with Castro and other Commies building walls to keep their people IN these "worker's paradises".
Build a huge trench with barbed wire along the top and make sure it's patrolled, heck, bring the troops home from Germany to guard it. We have the right to protect ourselves, and who cares what the Canadian or Mexican Governments think, they don't support us NOW, anyway.
After all the rhetoric on different threads about this, FD, I've come to believe that's the only way to go.
The cost of anything we build would be negligible compared to what we're paying now and what we'll pay when the attack comes.
If your home is filling up with water, the first thing to do is stop the water, then you can concentrate on the damage done.
So far we've done neither one.