Why go through all that expense?
I still think the most efficient approach is to invade Mexico. Move the farms to the workers, clean up their produce (which we all eat during the winter) so they don't use sewage water and control the chemicals. Pipe their
oil (they have it, they just don't know how best to get it) overland, take over their beaches, etc. Keep it as a third world terroritory, like Puerto Rico and Washington DC...just tax em but hold back on the vote.
Build a fence at the southern end...much shorter.
Donkey shows are better than camel shows.