"It's legal to build houses and farm food, neither is a significant fraction of our GDP, and some thought has already gone into making industries like that ridiculously scalable just in case there is some wild reason why a tenth of our infrastructure suddenly has to rebuild the other nine-tenths.  One year after dath ilan knows about Earth, we will have enough emergency arcologies set up to evacuate a billion people from Earth.  In two years we'll be ready to accept the entire population should that become necessary.  If we ran into a nicer civilization, I expect we would have reciprocal versions of the same arrangement, in case of asteroid strikes or alien invasions or ocean algae suddenly dying out."

"It's legal to build houses and farm food, neither is a huge fraction of our GDP, and some thought has already gone into making industries like that ridiculously scalable just in case there is some wild reason why a tenth of our infrastructure suddenly has to rebuild the other nine-tenths.  One year after dath ilan knows about Earth, we will have enough emergency arcologies set up to evacuate a billion people from Earth.  In two years we'll be ready to accept the entire population should that become necessary.  If we ran into a nicer civilization, I expect we would have reciprocal versions of the same arrangement, in case of asteroid strikes or alien invasions or ocean algae suddenly dying out."