[quote=@Willy Vereb]
<Snipped quote by Lucidnonsense>Depends on what do you man by that it's already a thing here.
The Federation seems like an interstellar equivalent of the EU rather than a strict one government system since nations like Chaptrap's Fomoria can exist in them.


[/quote]

Fomoria is more of a constituent planet within the Eos Federation or whatever it is. Maybe others have achieved some kind of autonomy but Fomoria is still ruled from Eos while probably sending a few politicians to the central government to voice its own concerns. We shouldn't get too bogged down in fictional, interstellar politics but that's what I'm going with. We can say it's a newer colony or something.