If the braceros have heavy equipment capable of knocking over shipping containers, you’ll need the Maginot Line, not a heavy duty fence.
As I recall, the Maginot Line was not a success. Please correct me if I am wrong.
Obstacles which are not under observation and covered by direct fire serve only to annoy an opponent.
“Now imagine me on The Maginot Line...”
https://www.youtube.com/watch?v=hSSBQWbF7R8