Even with people who are really cruel and doing a lot of damage in the world, you can wish them goodwill because you want them to understand true happiness and act on it. They’d have to change their actions for the better.

"As the Buddha said, discernment begins when you ask the question of someone who seems reliable: “What, when I do it, will lead to my long-term welfare and happiness?” Now you can interpret that on an external level, but you can also interpret it on an internal level. The external level is the practice of merit. Generosity leads to long-term welfare and happiness. Virtue leads to long-term welfare and happiness. Developing attitudes of universal goodwill [mettā] in the mind leads to long-term welfare and happiness. Those are attitudes and actions you want to develop because they help you see more clearly how your actions have an impact on your life. As you act in more skillful ways, life becomes a lot lighter. You feel a lot better about yourself.

There are a lot of people out there who, when they’re feeling bad about themselves, go see a therapist. And what the therapist should tell them is, “Go out and do something good. Go out and help somebody. Try to be more principled in your actions.” A lot of genuine self-esteem would come from that.

It’s the same with thoughts of goodwill. You begin to realize you’re living in the world without having any ill will for anyone, and you can base a genuine sense of self-esteem on that. Of course, it takes time to develop that attitude. It’s not like we’re born with limitless goodwill, but you can practice. You can ask yourself, “What is goodwill?” It’s a wish for happiness. Well, where does happiness come from? It comes from actions. So when you’re wishing for your own happiness, you’re hoping that you’ll act skillfully. When you’re wishing for the happiness of others, you’re hoping that they will act skillfully. And that’s a wish you can have for everybody.

Now, some people on your list are beasts. You might say, “Well, I’d like to see that person suffer a little bit more before they’re happy.” But it doesn’t really accomplish anything. Even with people who are really cruel and doing a lot of damage in the world, you can wish them goodwill because you want them to understand true happiness and act on it. They’d have to change their actions for the better.

When you can take that attitude, you’re more able to trust yourself in your dealings with other people, and you feel better about yourself. Other people can trust you more, and you can trust yourself more — all from just changing the way you act, changing the way you think. This is why they say that the practice of merit is really helpful in the meditation, because it gets you more sensitive to your actions and the power of your actions."

~ Thanissaro Bhikkhu "Insight Is Seeing What’s Worth Doing"