How so? Sure, there's a significant upfront cost to sending a rocket out to the asteroid belt, but you only have to do that once. Once there's a base with a rad

How so? Sure, there's a significant upfront cost to sending a rocket out to the asteroid belt, but you only have to do that once. Once there's a base with a radio antenna, machine intelligences can travel back and forth at the speed of light. And once you're in the asteroid belt, you have a huge amount of unclaimed raw material, unlimited space, and no gravity well to get in the way.