Redefined in greater detail:
Peaceful. These are economies that are best characterised as isolationist. They trade, they like others (?) but they do not deliberately start a war for profit and they thus have massive accountability and must have a democracy or constitional monarchy. They have a strong sense of patriotism.
Something else which I failed to mention is that these perfect utopis are rare. Governments will usually get more and more trade expansionist the larger they get. For one reason - how do you hold together a bunch of planets that may for all you know, dislike each other. I forsee Peaceful empires as being small groups of 3-4 planets settled by a particular ethnic group, like the British could settle 3-4 islands and then those islands would willingly be part of Britain. To not have a trade empire they would have to willingly be part of it... you can see how amazingly rare it is for these to happen.
And it becomes even more difficult once you realise that injuries would be dealt and received over the course of galactic history. So it could end up like the nations on earth, being asked to join together...
Trade: Trading empires result on massive abuse of human rights. They are corporate governments. The cheaper it is maintain someone for making profit the better. If profits are threatened, massive fleets entail. This could become quite awful... quite awful indeed.
On the plus side, they will likely favour democratic institutions because of the effeciency bonus. Atleast at home. on the colony worlds they will have second class citizens and likely slavery. Also they would rule with client states. they would extort money... it is possible to make a fleet into one huge profit making machine I guess. You could threaten to blow up a planet unless you get 50% of it's GNP. And other such charming things... I suspect Trade empires would vary wildly. The only thing we know for sure is that they'll be coming from a democratic institution so they'll probably be democratic on the outside. It depends how it turns out. I'm sure we'll have plenty of villain empires that are just as bad, if not worse - than warlike ones.
I should note that the slaughter of above 6 million people in India during a famine which the British could easily have averted went practically unopposed by it's democratic institutions... the same institutions which abolished slavery about a hundred years ago... Can you imagine anything like that happening today?
There was the famine in Ireland... above 1 million people... on their doorstep!
But in Britain people enjoyed rights greatly. I think these governments will be Republics. Also note - although they do not need effeciency as much as el peaceful they will still like it.
In this empire, large navies will come with it. Because of all your territorial acquisitions which you have to defend and stuff. You will be gathering tribute not only from client states, but from states you are terrorising. Or colonising you are forcing to stripmine.
But remember, it is not economical to wage a war on a colony that doesn't actually threaten your navy. So I predict the Trade Empire may actually end up with a 'heart' in a very real sense. They would have their fair share of planets, but they wouldn't feel the need to go out of their way to conquer one if they could simply make it a colonial acquisition. I imagine the root of Trade empire in space would be a home planet, that star system, and then several star systems around it which they've intimidated. These star systems would eventually be joined and integrated as nations, with the occasional rebellion and have sympathetic governments installed. Their main production would be on those planets.
Outwards they'd find other colonies where you'd land some troops and make it an outpost. So it would progress continually and continue to seperate - since trade empires know that they want their military to be centralised because it's the cost effective thing to do. Eventually things would get more and more massive. The outposts will become internal worlds, internal worlds will become core worlds. Democracy might even have a chance (or atleast a republic.) Once the internal worlds get accepted by centuries of association they will need representation and that is what they'll get.
Then you'll reach a point where you have a federation. States that are colonised at the outskirts go through an initial process of barbarity, become familiar and then get integrated by force. I'm still thinking... this theory doesn't quite hold up. India never became integrated into Britain. Scotland maintained degrees of seperation despite being next to Britain.
I suppose it's feasible you could get your internal circle of same ethnic planets. These would form your interior parliament. The centre parliament would experience ruptures depending on how close they really were. Then there'd be lines of tyranny extending outwards. You could have something like a hundred star systems under your control, massive fleets, robotic armies, and all of it coordinated from this tiny star system. It's cost effective!
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