Here's the essence of it: you can trust America's crème de la crème, the most elevated, responsible people, no matter what weapons, what powers, you put in their hands. No need to constantly look over their shoulders.The reason the United States was founded on the principle of checks and balances is that NO ONE in government should be afforded unrestrained trust. When the rich and powerful are granted (or grant themselves) absolute power, the outcome will never be good.
Placed in the hands of evildoers, those weapons and powers could create a living nightmare; controlled by the best of people, they lead to measured, thoughtful, precise decisions in which bad things are (with rare and understandable exceptions) done only to truly terrible types. In the process, you simply couldn't be better protected.
And in case you were wondering, there is no question who among us are the best, most lawful, moral, ethical, considerate, and judicious people: the officials of our national security state. Trust them implicitly. They will never give you a bum steer...And in case you wondered just how we know all this, we have it on the best authority: the people who are doing it — the only ones, given the obvious need for secrecy, capable of judging just how moral, elevated, and remarkable their own work is.
~ from Why America's Killer Drones Give Our Government Too Much Power by Tom Engelhardt ~
It doesn't matter how noble, moral or ethical any given leader is. He or she will surround him or herself with sycophants and any thought of any degree of objectivity will fly out the door. Government then becomes a large echo chamber in which what the leaders deem to be ethical and legal becomes so simply on their say-so.
This is one of the key variables that separates dictatorships from democracies. The former expressly eschew the idea of bona fide checks and balances because nothing should impede the dictator or ruling party from doing whatever in the hell they want to do! In true democracies, however, the system of checks and balances [imperfectly] restrains the various branches of government from overstepping the authority vested in them by the citizenry.
While the US has not devolved to the point of dictatorship, we certainly are moving that direction on the spectrum. At the rate we're going, we may arrive at that point within a generation or two.