That's it.
We're at war.
The ultimate "No Trespassing" device.
Fine. WHile you're busy programming your autonoumous robots to be autonomous, my old-fashioned, gun-armed, real-flesh-and-blood military will occupy your land and steal your riches. Afterwards, we'll reinstate commerce.
Youwould have failed because you cannot program a computer for every contingency and my human generals would have run tactical rings around your robots utilizing their Mark I, standard-issue brains.