Quote:1. Distance. Even if their drives are faster than fennish ones, their home system is a long way away from our centers of power and vice versa. Raw materials might be available on-site, but all the needed equipment would still need to be shipped pretty much the whole way.
If we're that close, then terraforming their homeworld will be an easier job than terraforming venus or Mars... and vice versa. ("It may be a frozen, twilight, desert hell, but we can qxn$rk-form it in a few decades...") We're going to have to come up with a few in-story reasons why the extremists on both sides wouldn't be allowed to try some planetary engineering of the other race's homeworlds.
2. Hostile natives. I imagine that the crabphants would have just as many objections to a terraformed homeworld as we would to having Earth turned back to the Pennsylvanian - and as violent ones.
3. Morality. The moderate and bleeding-heart lobbies would never hear of it.
Besides, Drogn's description of them sounds like a low-gravity bauplan to me. If the next world out from their homeworld happened to be a largish one that they avoid because the gravity is dangerous and unpleasant...
Ja, -n
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"I'm terribly sorry, but I have to kill you quite horribly now."