1 sq mi = 5280ft x 5280ft = 27,878,400 sq. ft.
1 ac = 43,560 sq. ft.
27,878,400 : 43,560 = 640 acres
640 : 4 = 160
160 Acres would be 1/4 of a square mile.
40 Acres is 1/4 of 1/4 of a square mile.
There are 16 40 Acres squares within 1 square mile.
Isn't sq mile = 640 acres, 1/4 square mile = 160 acres.
Anyway, they probably aren't home right now but it still is something that we can break.
Get dam and power plant, maybe divert river upstream. FAE to get their attention, cluster munitions on buildings and helipad, napalm the cave entrances - then bring in the Buffs for rolling thunder.
We probably won't kill many but they wont be able to use that camp for a while.