There are two kinds of bad people. There are people who are bed because they lack morals. There are people who are bad because they have the wrong morals. They are very different.
Most people who are bad are bad because they lack morals. Criminals. Drug dealers. Thieves. Etc.. These people don’t do bad things out of a genuine belief that stealing or hurting others is the right thing to do. They do it because they do not have morals and/or because they are too weak to live by their morals. They may well have circumstantial justifications for their crimes but these are usually paper think and only serve as rationalisations. These people are like animals. They respond to simple stimuli: pleasure and pain. Hurt them when they do evil and they will stop. Establish dominance over them and make them fear you and you will have peace. If you’re faithful try to change them but changing peoples character is hard.
Some people who are bad are bad because their morals are evil. Jihadi’s. Ideological killers. Etc… They do evil knowingly and willingly, believing it to be good. They differ from the average criminal. The criminals motivation is selfish. The ideologically motivated evildoers is not and some will be willing to pay for their beliefs with their lives if that’s what it takes. Hence dealing with them is a different matter. Force alone is seldom sufficient and bloodshed alone can’t kill an idea.
That’s a lie. It can and has. The soviets killed whole peoples. The mongols put Baghdad to the sword. The CCP smothered Falun Gong. If you’re willing to be brutal enough, to spill enough blood, you can certainly kill an idea. Modern democratic states are not so that option isn’t worth discussion. (And for those who think it is, remember that a state which can liquidate millions of it’s citizens at will may well be more horrific than whatever ideology/group you personally dislike.)
I don’t know what else to say so I won’t. One other thing. It’s not discrete. Most things aren’t. It’s a scale and many monsters will fall somewhere in the middle. Still, I’ve found the model useful.