Whenever the subjects of Charles Manson, Jeffery Dahmer, and the like come up, I start thinking - These men were undoubtedly evil people, but they certainly were not the worst people to ever exist on the planet. I wonder who was the worst, most evil person to ever exist on earth? We will almost certainly never know. The worst person to ever exist was probably so good at being evil, that he managed to escape detection.
It's all too easy to give the title "Worst, most evil person to ever exist" to the likes of Hitler, Stalin, or Mao but these people were merely leaders of tyrannical governments. All leaders of tyrannical governments practice the same type of evil to some extent, but none of them could have ever pulled off what they do/did on their own, and they could have never pulled off what they do/did if they were leaders of free societies. That takes the help of millions of willing (and unwilling) accomplices and the power to silence all who disagree. The form of government they led, was more evil than Hitler, Stalin, and Mao, themselves. This paragraph alone is reason enough to actively reject all forms of authoritarian government.
OK, so when you take tyrannical leaders out of the mix, who was the most evil person ever? As I said earlier, we probably will never know, BUT we may just find out who were the most evil people to ever be exposed, IF Trump makes good on his promise to do a little digging.
Check out this video at It Ain't Holy Water. Who knows how far and deep this evil goes?