“So what might really aged civilizations do? Disperse, of course, and also not attack new arrivals in the galaxy, for fear that they might not get them all. Why? Because revenge is probably selected for in surviving species, and anybody truly looking out for long-term interests will not want to leave a youthful species with a grudge, sneaking around behind its back...”
This is why you want to have colonies and habitats outside the Sol system especially,
Ah, you have been at Atomic Rockets, reading up on aliens? The only reason they came up with.
http://www.projectrho.com/public_html/rocket/aliens.php
“So what might really aged civilizations do? Disperse, of course, and also not attack new arrivals in the galaxy, for fear that they might not get them all. Why? Because revenge is probably selected for in surviving species, and anybody truly looking out for long-term interests will not want to leave a youthful species with a grudge, sneaking around behind its back...”
This is why you want to have colonies and habitats outside the Sol system especially,
https://www.researchgate.net/publication/283986931_The_Dark_Forest_Rule_One_Solution_to_the_Fermi_Paradox