Yes, the Sona were out of control and had to be stopped, not to mention reported to starfleet, which was in the dark.
Yes, the movie has plot holes. They all do.
Insurrection threads make my boobs firm up.
in what way were the Son'a "out of control?"
The first part of the movie showed them calmly and completely cooperating with Starfleet on the "duck blind" mission, a mission that required a lot of patience. Again, the Son'a ONLY retaliated in response to Picard's sabotage of the plan, they had been nothing but cooperative up to that point.
And Starfleet wasn't in the dark, Dougerty was an admiral who was acting on orders from the Federation Council itself.