You walk into the room. A psychologist welcomes you and explains that in another room there is a man taking a test on remembering words.
You're placed in front of a series of buttons, and every time the psychologist tells you that the man has made a mistake, you deliver stronger and stronger electric shocks to him.
As you press the buttons, you can hear the man in the other room yelping. At higher levels the yelps turn to shouts. The man starts knocking on the wall, asking to be let out. Now you express some concern, but the psychologist tells you you must keep going, and so you do.
As you keep delivering stronger and stronger shocks, his screams turn to pleas for mercy. You continue to shock him, and at the very highest levels he falls ominously silent. You continue to press the highest button again and again.
Don't think you would ever do such a thing? That's what a lot of people say, but when this famous experiment was conducted, psychologist Stanley Milgram got a different answer. Sixty precent of his subjects did indeed shock the man in the other room past the point where he seemed to be dead, because they had been told to do it.
In reality, the buttons were not connected to anything; the experiment was designed to see how far people would go when told to do something unethical by a perceived authority. As Milgram observed, if the tendency to obey authority is this strong for a psychologist, one can only imagine how much more powerful it is in the case of a political or military leader.