The main wall should be 30ft tall.
There should be also be an extra 20ft on top of that that is comprised of thin black spires that are near razor sharp.
Sonic microphones should be placed every 20ft and be monitored 24/7.
The American people should be able to view any section of the wall, on the internet, at any time.
There needs to be two walls....with a road in the center for BP agents.
Lots of razor wire, small missiles to take down any drone passing from south to north....this is easy. Also easy to just patrol with drones that can destroy other drones...they have them now.
Sonic microphones
Ancient truth: An obstacle uncovered by fire is no obstacle
Although this is politically impossible the most humane barrier is a mine field. Each year many hundreds of illegal aliens die in the deserts of the Southwest trying to gain illegal entry into our nation. Last year it was about 400 bodies found. The real number is much higher. Their bodies lay undiscovered in the deserts. Only the insane would try to cross a mine field. Thus these many hundreds of deaths would not happen in our deserts. The caravans of illegals would stop.
What is more humane, a mine field that would kill just a few insane people, or hundreds of deaths in the deserts due to thirst and heat? It is not a nice death. My numbers of deaths does not include that of the caravans and the rapes and indignities committed against the women in these caravans before they reach our border.
plus some artillery to break up enemy formations and pick off stragglers