(TGMC}

Secret History

TerraGov

TerraGov's opening colonies and diverting immigration to keep everything outside of solsys from being a member by keeping population low.
Multiple member states are secretly under martial law.
At least one extra-solar colony is being used as a slave colony to work with VERY dangerous things.

They're based off of alien technology. No, for real! I'm not CRAZY!
The "blood rage" affects all synths after a random time. Most were after a few months, but it could happen now.
Of course someone dismantled one and is making more in secret. Who? Up to the admin who wants to put a synth manufacture facility planetside for 'rines to shoot up.

Of course they're conquering independents. It's so easy to knock them over, why not grab as many as you can!
The Confederacy is on the brink of fracturing due to tensions between the Big-3.
The ICC runs dedicated atrocity squads on independent worlds posing as TGMC personnel, then comes in to clean up the mess and take over.
There's a fourth, hidden member, one of the lost first-gen colonies.
They have a treaty with an alien race and are trying to sell out the rest of humanity.

The Sons of Mars are getting ready to leave the ICC and make a go of it on their own. The ICC really wouldn't like that...
The Sons run a gurreilla academy, with some excersizes being live-fire deniable raids on TGMC outposts.
They're searching for STC.. I mean, LOST TECHNOLOGY so as to regain the glories of the IMPERI... something they had before. Totally not techpriests.
The Sons have a working BLUEspace teleporter and drive design, one without all of them pesky downsides.
The Sons have began experimenting with viral plagues, in order to drive down the TerraGov population advantage.