[miele man]

I suspect the costs may be predicated and guesstimated upon the costs for constructing a mile of interstate road. How accurate this is for construction on our southern border is debatable.

See this: “In 1996 dollars, the Federal Highway Administration has calculated the “weighted rural and urban combined” costs per mile of interstate highway to be $20.6 million.(9) Other highway construction normally ranges from $1 million to $5 million per mile, but in mountainous regions, like West Virginia, the costs can be as ...”
Highway Construction Costs Under Government Provision
www-pam.usc.edu/volume2/v2i1a3s2.html

[Mr. K]

but we don’t need to build a cadillac all at once

Start with a two fence barrier with a 100 yards of groomed sand between them, and patrol vehicles, that cruise back and forth. Anyone between the fences is in the wrong place...

Rapid response teams for any footprints seen. Drones fly overhead. Cheap and fast.

THEN build it up in the bad spots.