: I've always assumed that MIDA were behind the battleroids on the Marathon,
: though exactly why they'd want to put them on a colony ship instead of
: keeping them for their own use on Mars/Earth is a bit more mysterious.
: Were they planning to take control of the colony and run it according to
: their own ideals? Was it to keep some battleroids safely away from the
: main UESC/G forces in case the main MIDA forces were defeated? That
: question I can't come up with a satisfactory answer for, along with
: "Why weren't the battleroids active (as in, revealed to be
: battleroids instead of just really strong random people) until the Pfhor
As for why weren't the battleroids actively taking over Tau Ceti right away? We do learn that MIDA was known for long rang politicking, so they don't mind being patient. My guess would be that since Tau Ceti colony is only 7 years old when the Pfhor attack, that MIDA was waiting for the UESC to build up the colony's infrastructure, establish factories, farms, hospitals, etc., and then use the battleroids to take over once all of that is finished.
Although Leela does tell us, "I'm certain the real answer lies somewhere in the tumultuous, back-stabbing politics of Sol during the early twenty-fourth century."