That’s ~$75,000,000 per mile. ($147b/1,951)
The southern border needed to be totally militarized 30 years ago. The damage is done and the demographic trajectory is irreversible save some presently unknown/black swan event.
Best we can hope for is Balkanization and separation.
That’s essentially my conclusion as well.
If I have to live in a Socialist nation, it will be one with better demographics than here.