[drran]

> The first colonists will of course need to bring stuff with them

IMHO, first thing sent will be a universal Assembler, which will produce stuff and clone colonists. If a woman can give birth to a baby in 9 months, we can create a "3D printer" which will self assemble other "3D printers", which then produce mechanisms, computers, and colonists.

[svachalek]

Absolutely. Any civilization that can't produce such a thing has no business crossing interstellar distances.

The "protomolecule" from the Expanse series is an even more effective if frightening version of the idea, an interstellar virus that hijacks any local biochemistry to bend it to its purposes.