Then imagine a single entity that has every domestic text, phone call, and email ever sent, searchable and indexed, on any politician, judge, or candidate. It's far, far, more power than merely spying on foreign powers.
That’s hardly unique to the US. Other nations’ intelligence agencies tend to attract the aristocracy, e.g. all the Oxbridge alum at MI6/GCHQ.
I read a book recently about a young (19!) year old tank commander in WW2 and he was told by his CO when arriving in Normandy that his life expectancy was 10 days.
https://www.amazon.co.uk/Tank-Action-Armoured-Commanders-194...
There is a lot of evidence that the CIA is doing whatever it can to ensure that the %1 of American society get their way with the world, however. That's not the same as 'serving country and government', by any stretch of the imagination.
There is in fact a lot of evidence that they serve the country.
The CIA has deep ties to the American upper classes. And probably serves their interests over the states. Or their own interests. Aldrich Ames was living well beyond is means for years. A good supposition is people at his level routinely trade intel to 'friendly' government an corporate interests.