what happens when the market fixes its supply chains with private police forces that are entirely unaccountable to local governments, and purely protect the rich? That's what's happened to South Africa.
But there are numerous solutions between the current situation and what you describe. Better locks, housing the homeless, reducing the amount of junk we import, etc.
I remember as a kid trains had cabooses (a sign of more employees). But of course that has all been optimized away. I’m guessing the skeleton crew is completely unable to secure the train if they wanted to.
Edit: downvotes for saying that the US has handled the identified problem in the past? (Which was a slippery-slope comment, anyway.)