But this logic doesn't explain why we need the NSA to spy on its own citizens? I mean, sure if someone else is spying on you, you need to spy on them. But if someone else is spying on you, you definitely don't need to spy on yourself.
Sure but that’s just a typical example of abuse of power. The initial comment was about dismantling such institutions.
Well I also questioned whether they should be given as much power, since it can lead to abuse. Would be as simple as changing a law so they can no longer abuse their power. And if it's not that simple, maybe you have to question why.
I would assume that NSA spying is used primarily for insider trading and other forms of market manipulation.