People don't have a mechanism to "inject civilization" into Mars either. Pushing massive quantities of ozone into the stratosphere sounds solvable in a year or

People don't have a mechanism to "inject civilization" into Mars either. Pushing massive quantities of ozone into the stratosphere sounds solvable in a year or two, since we already know how to make it. Making a self-supporting Martian colony is a multi-generational project that we can't even begin yet. Let's do it, but these other threats are going to be extinction-level for a long time.