I'm talking about cooperation in the context of the prisoner's dilemma example, not cooperation in general. I don't need or want to cooperate with people who have nothing to offer me, my family, or my community

Selfish take

And before you downvote me, explain how the concept of charity maps to non-cooperation unless you yourself has something to gain

See, now thats at the heart of it isn't it!

What /would/ someone have to offer you, your family or your community? What do you value? What does your community value? How do you know folks have nothing to offer?

The person you’re responding to may not believe those things, and may not want those things or think it’s possible or reasonable. Let them speak about it at least before assuming that group affiliation means those things.

FWIW I believe dehumanization is a horrendous thing, especially when aimed at relatively powerless minorities.

The people currently in power do believe and act on those things. Claiming they aren't the bad guys (and especially voting for them) demonstrates tacit acceptance of those beliefs and policies whether you like it or not. You don't get to support people who do bad things and claim you don't agree with the bad things.