The Romans built a wall around Jerusalem in three days. Barriers can be erected quickly if there is the will and man power. Hungry fenced off it’s borders in a matter of weeks.
I believe we should make sure the wall is secure and sturdy, and I would think our military could build it. Seabees build military constructed compounds all the time, and is part of Navy.
In 3 days...lol. It’s not like we have a pile of rocks laying around down on the border. Everything will be shipped in, and just getting it ordered take time. This is the modern shipping era, not a just a go to work in past history! Sadly!
The US/Mexico border is 10,317,120 feet long.
At 200 foot separation; we’d need just over 50,000 armed men to stand their ground.
Do we have that many available?