Regarding the trustworthiness of 'three letter agencies', two of them (DoD, JCS) approved plans for another (CIA) to commit terrorism against American civilians in order to justify a war against Cuba [1].
They could ultimately have America's best interests at heart, however you can be certain that their public statements have no standard of truth and are made to serve a covert agenda.
One operation from over 50 years ago is your example? Back then the spooks were doing far worse, conducting operations against domestic civil rights groups.
That's a little different than a public DNI statement on behalf of 17 different agencies pointing to Russian attacks, corroborated by multiple other nations, in an era of wide-spread whistleblowing that would uncover a large-scale conspiracy.
I agree Russia is the most likely perpetrator, but it's all circumstantial from the evidence I've seen, and there's clearly a large sociopolitical impact from this hack.. hence it's substantial enough to be framed for some purpose.
I'm merely pointing out that we should question it when the U.S. government says "They did this!", as they've clearly tried to lie about it before in dire circumstances.
I wish I had more recent examples to give you, or examples that were actually executed on, however I think that'd be rather dangerous and impossible to obtain.
> One operation from over 50 years ago is your example? Back then the spooks were doing far worse, conducting operations against domestic civil rights groups.
Or torturing Americans civilians for eh... testing whether interrogation techniques would work on the real enemy(tm) as well.
They could ultimately have America's best interests at heart, however you can be certain that their public statements have no standard of truth and are made to serve a covert agenda.
[1] https://en.wikipedia.org/wiki/Operation_Northwoods