During the Bakumatsu period, the sonno joi ("Revere the Emperor, Expel the Barbarians") movement was used by the anti-Shogunate forces coalescing to topple the Tokugawa bekufu in the run-up to the Boshin War. And yet, when the Meiji Restoration actually took place, the new government formed by the victorious Satsuma and Choshu domains - who were as acutely aware of Japan's relative vulnerability as the last shogun had been - promptly jettisoned any such talk in favour of a full-scale effort at modernization... to include abolishing their own home domains and replacing them with prefectures.
Similarly, I think of how the Star Adders used the Steel Vipers to evict the Invader Clans from the Homeworlds... only to turn on their former allies at exactly the point at which they ceased to be politically useful.
Alas, just as not all of those who fought on the Boshin War were content in the new Meiji-era Japan, leading to the ill-fated Satsuma Rebellion, the legacy of the Bloody IlKhan had by no means been fully digested as of The Wars of Reaving Supplemental - as seen with the rise of the Bastion and Aggressor factions.
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In any case, the Star Adders are, or were, supposed to be the self-proclaimed "grown-ups" in the room: using one of their Galaxies as an Inner Sphere OpFor; pushing to have all of the Clans go together during Operation REVIVAL; and, when that effort failed, bidding their entire Clan to be part of the invasion force.
But even if that would still be the case - as in, the Adders plan to essentially migrate to the Inner Sphere en masse - there's still the question of how to prepare for such a massive undertaking. Not least with so much to be done in order to rebuild the Homeworlds to the state that they can provide the resources needed to undertake such a reverse-Exodus.
And there's still the question of what to do once they get there. Taint or no taint, there is going to have to be some sort of plan in place to deal with their would-be Inner Sphere subjects in a way that is not entirely self-defeating. They are supposed to be the level-headed ones; surely that should also include taking the time to figure out what a would-be Star Adder Occupation Zone would look like?
And there is the question of how eager - or not - some within the surviving Homeworld Clans might be to say goodbye to Strana Mechty for good. What if, at the time a new invasion/migration is seriously being discussed, there are more than a few who are not ready to abandon the Pentagon Worlds and Kerensky Cluster, if the logic of the Adders' argument is to be followed through with?
Trying to answer any or all of these questions, and more, could help explain why it's taken so long for any contact to be made wit hthe Homeworlds as of 3152: it's taken that long, and more besides (such as, say, news about the McKenna's Pride and of the entombing of General Kerensky's body at Unity City to reach Strana Mechty), for this process of evolution to play out.
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Personally, I would suggest that the Coyote "problem" be dealt with by leaving them behind as the last Wardens: joined perhaps by whichever Cloud Cobra Cloisters vote to stay at home. While seeing the Star Adders, the Stone Lions, and the other Cobra Cloisters - to include their respective civilian populations - set out to make a permanent move to the Inner Sphere.
This would be the first time a Clan migration took place entirely on its own terms, rather than being the result of a rushed timetable (or a prompt expulsion).
I noted this in a separate thread, but I'd place their would-be OZs facing the old Exodus Road: with the Stone Lions on the far side of the Rasalhague Dominion from the Hell's Horses; the Cobras placed next door to the Raven Alliance; and with the Adders holding the centre position between the two.
That might lead to some unexpected alliances, if the Bears and Ravens were to see the Combine as the lesser of two evils. But then... what if the Horses end up siding with the new arrivals, and push to link up with their Stone Lion counterparts by cutting through Dominion space?
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Overall, I'd worry that, the longer the Gordian knot of what to do with the Homeworld Clans is left, the more difficult it might seem to untangle it.
Perhaps, at some point, this knot should be cut: better that then keep them off the board for the foreseeable future.