This may be true in the abstract, I agree, but out there in the world, you don't have to stray too deeply into kook-dom to realize that, unsettlingly often, we're (the US) the guys responsible for the creation of the conditions in which warlords and drug cartels operate in the first place -- and almost as frequently, of the groups themselves. There are no drug cartels without a War On Drugs, and indeed, the CIA has been shown to be deeply involved in cartel activity itself. (See the Kiki Camarena story, Gary Webb's work, and the story of Sister Dianna Ortiz. All mainstream sources, no whackjobs. The recent-ish Camarena Netflix documentary "The Last Narc" is terrific.) So you could make a compelling case that if we didn't get our hands dirty in these areas at all, we wouldn't need a CIA or NSA to manage the inevitable consequences when the actors involve start behaving in ways we don't like. (I'm told they call this "blowback".) And indeed, this is exactly the point. It's a genius business. It's like the guys in Amsterdam who own both the cannabis coffee-shop and the kebab place next door to it. Revolving door operation. Prints money!
> That only works in the context of strict oversight and principled direction by an incorruptible chain of command and leadership by elected officials given privileged access.
Respectfully, this is impossible. Human beings cannot do this. No one is incorruptible, and there are too many people with an interest in meaningful oversight never existing, starting with these little mafias themselves. The real-world record bears this out: there is no meaningful oversight, from congress to FISA to your local cops using StingRays. They're just not going to tell you what they're doing. And if you bother them too much about it, well, let's just say don't get on any small aircraft. This is an open secret in DC. Look, even Chuck Schumer knows: "Let me tell you: You take on the intelligence community — they have six ways from Sunday at getting back at you."
As I've said in other threads: if you ask a bunch of people to get world-class-good at lying, stealing, betraying, and murdering, and they then start doing those things to you, well, there's no one to blame but yourself.