It does make you wonder if they decided it would be best to kill some Americans in California to make a point that they needed power.[1]
We know they had intent to protect their powers.
We know that they are willing to train and create terrorists in order to help make the point that terror is a real threat.
We know they lie and can do so with out any punishments by our government.[2]
The real question is would they murder Americans to help keep that power.
I still find it hard to believe that they would be willing to kill Americans in order to keep these powers, but I am finding it harder to keep this belief.
After COINTELPRO law enforcement as a whole in both the US and other countries moved to a subversion model as opposed to an adversarial model. This is why the FBI or local police have infiltrators or paid informants in virtually every activist group in the US, regardless of whether or not those groups are actually affiliated with terrorism -- if they ever start leaning that way, LEA will step in and disrupt it from the inside.
The way this works out in practice is that every agent sees an opportunity to advance their career by manufacturing threats. So they have their infiltrator agent or their informants stir the pot, see who's "really down for the cause," get as deeply embedded with the group as they can (going so far as to have children with members in some occasions), and gradually shift the group towards extremism, or if the group won't go along with it, whoever they can splinter off and radicalize.
Once this person has incriminated themselves enough, they get arrested and charged with terrorism.
I'm not going to cite any sources because you could easily find reasons to dismiss them. Certainly, I don't know of any listing of all arrests for terrorists accompanied by all the case details, so I'll certainly never be able to provide quantitative evidence of this very real trend. Also, I think that looking all of this up and finding it out piece by piece will be valuable for you -- it's very easy to dismiss a fully formed theory such as this comment, but it's more difficult to dismiss all the little pieces of evidence you build up over time. Maybe keep a document with all the incidences you find, to prevent yourself from dismissing every single one of them as "only about one case -- not a trend" and by induction, determining there is no issue.
And another one: https://theintercept.com/2015/04/29/tamerlan-tsarnaevs-path-...
More: https://theintercept.com/2015/02/26/fbi-manufacture-plots-te...
And more: https://theintercept.com/2015/02/25/isis-material-support-pl...
Then there's this: https://theintercept.com/2015/01/16/latest-fbi-boast-disrupt...
And this: https://theintercept.com/2015/06/25/fort-dix-five-terror-plo...