I think this one came from a discussion of Machiavelli I was listening to on the Diane Rehm Show. A professor of political philosophy was asked, essentially, why should politicians be the only ones we expect to act in Machiavellian ways? The answer was essentially that a large number of people in a representative democracy expect their leaders to get their hands dirty in ways that we would be uncomfortable doing ourselves. We hand the moral baton off and say “don’t tell us what you’re doing. We don’t want the burden of knowing.”
Personally, I think that’s a ridiculous cop out that has caused far more trouble in our history than it’s prevented or solved. Give me transparency, and an aggressive investigative media.
But the one indispensable thing you give up when you say “don’t tell me what you are doing” is knowing how well (or how badly) those secret actors are doing their jobs.