Humanity has never managed to communicate with the Xenophobes and only has the latter's attacks to learn about them.
Later books detail humanity's conflict with itself, and a race of artificial beings called the Web.
It's set in the 26th century and involves fringe-of-empire settlers breaking away from an overbearing Earth government dominated by the Japanese Empire [...] which had the sense to grab the high ground of space when the U.S. abandoned it in the early 2000s.
Most of the first book revolves around a war with some VERY strange aliens, while the rest pit frontier rebels against the Empire[,] [...] then involve both in a struggle against a malevolent AI machine threat from the Galactic Core."
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