The deal with Helena was the opening of the situation. The personnel of the Kepler army were readily available and, boosted by Kepler's intelligence, they had a reasonably high guarantee of combat effectiveness. At present, the order was maintained by the Mecha, which was usually sufficient. However, once extraterrestrials with Heavenly Martial capabilities appeared, things became extremely troublesome. To maintain Kepler's development, strict demands couldn't be overly imposed. In reality, even strictness was pointless as peripheral merchant ships risked being plundered as soon as they left the Pleiades Starfield.
Both cargo and humans were potential targets for plundering, from beasts and others alike.