Hmmm I think what the QCP did was a really good war act against the corsair !
Let's talk strategy...
Bretonia is actually at war against the corsairs and the KNF. What's interesting here is the corsair side.
The corsairs do not produce enough food for their people and have to get lot of it from different suppliers. The only faction that can fit this place is the zoners. They have lot of food, they produce it in mass.
The gold from bretonia on way to the Rheinland is disrupted and moved to Tripoli, so the corsairs have enough money to buy the zoners all their food to a high price. The Bretonians can't hold the convoys to the Rheinland due to the economical treat it would provide so it can't make hungry the corsairs this way.
So bretonians know about the corsairs need the zoners to live, so instead of attacking the bigger treat from front against overarmed crafts, the QCP hit them from behind, zoners in a system where the corsair influence is at his minimal.
Kill the zoners and you will kill the corsairs, that's all !
Now on corsair. Why do you think the corsairs are present and applying their pressure on the zoners ? It's about to survive, feed themselves ! As I just said, kill the zoners and you will kill the corsairs. The corsairs deployed a defensive force against the QCP to that aim, survive.
I do not blame the QCP for their zoner hunting, I even applaud them for the tactics.
Bretonia and Corsairs are at war, a bloody one, that's how all of those event started.
If the Privateers still want to leave Bretonia a chance to leave few peace and redirect his forces against Kusari, they must continue their massacre.
In short, zoners must suffer or bretonia will die !