[jongjong]

You're leaving out the cost of getting caught with risk factored in.

Also, if targeting small individuals, it's rarely one individual that's the issue, but a whole group. When Stalin or Hitler started systematically exterminating millions of people, it was essentially done algorithmically. The costs became very low for them to target whole groups of people.

I suspect that once you have the power of life or death over individuals, you automatically hold such power over large groups. Because you need a corrupt structure and once the structure is corrupt to that extent there is no clear line between 1 person and 1 million persons.

Also I suspect only one or a handful of individuals can have such power because otherwise such crimes can be used as a bait and trap by political opponents. Without absolute power, the risk of getting caught and prosecuted always exists.