Part 11/12:
Beyond technical details, Kirtley offers a philosophical perspective. If advanced civilizations exist elsewhere, they likely harness fusion, powering stars and, potentially, their entire planetary systems. The Fermi paradox—why we haven't encountered extraterrestrial life—may reflect the technological challenges and potential self-destruction of civilizations wielding immense power.
He speculates that civilizations may focus on expanding their cognition—via Matrioshka brains or Dyson spheres—much like growing superintelligent AI, rather than physically colonizing space. Fusion is thus not only a technological revolution but a step towards humanity's place among cosmic civilizations.