Of course they aren't ready for it, of course we'll spoil the place. Are they any more ready for World War Three? You seriously think we could mess the place up more than they're doing at the moment? When they're not actually out slaughtering each other they're inventing ingenious new ways to massacre each other more efficiently in the future, and when they're not doing that they're committing speciescide, from the Amazon to Borneo... or filling the seas with shit, or the air, or the land. They could hardly make a better job of vandalizing their own planet if we gave them lessons.