I don't believe in "punching up". The argument seems to be that oppressed groups have the privilege of "punching up" to members of groups that have traditionally oppressed them. I think this is unethical on several grounds. As a liberal, I believe in the same human rights for all human beings. The problem, as I see it, is that certain oppressed groups' rights are being oppressed, such as the right to be treated with respect and dignity and the right to justice. That's wrong, but so is "punching up" in my opinion.
1. Members of any group do not necessarily share all of the qualities of that group. We all know that it's prejudice to think they do. If it's wrong to be prejudiced against one group, it's wrong to be prejudiced against any group. When we say that a group has traditionally oppressed another group, we mean...- (a) that group is typified by people who oppressed the other group, not that every member of that group did. There's a huge difference between how, say, Jefferson Davis oppressed black slaves and how white Quakers working for the Underground Railroad helped them escape slavery.
- (b) By "traditionally" we mean used to and to some extent still do. There's a big difference in how most white Americans treated black people in, say, the 50's and how we do today. There are absolutely problems (e.g. cop shootings) that cannot be ignored, but this is uneven across the white population.
So, it's unfair to assume that, say, all white people deserve to be "punched up" at. Donald Trump? Probably deserves it! Jefferson Davis? Get me a Tardis and I'll have words with him myself! However, in most cases, I think it's wrong to lash out. Ditto for men, straight people, Christians, and so forth. But many of us were taught, in our homes and in school, that racism, sexism, homophobia, and religious discrimination are wrong. So, it's not fair to any given individual of a so-called "oppressive group" to treat them as if they're all uniformly guilty of active oppression that deserves retaliation. To "punch up" indiscriminately is, first of all, wrong because it's prejudiced.
2. Hurting others is typically wrong. Even if we're not physically harming another, emotionally abusing them is typically wrong. Exceptions are just that: exceptions. We have a right to use self-defense, for example. If someone is being particularly nasty to you, it may be that saying something nasty to them is what it will take to get them to back off. Fine. As a non-Christian, I admit that I've occasionally gotten rather nasty with particularly abusive evangelicals who told we I was going to "burn in Hell" or the like, but I wouldn't do that if the evangelicals were nice or if the Christian, in question, had a live-and-let-live attitude toward me. Hurting someone just because they hurt you is still wrong, because two wrongs don't make a right. In this case, we're talking about abusing others because their group hurt you, even if the person you're hurting didn't personally hurt you. That seems even worse to me. Hurting someone because they hurt you is understandable, even if it's wrong, but for me to, say, lash out at any old Christian just because some Christians are jerks to me would not even be understandable. It wouldn't be fair to them.
3. Everyone has human rights. Even if some folks are members of groups that have traditionally oppressed you, they have the right to justice and to be treated with respect and dignity. To abuse them is to violate that.
4. It's bad, strategically. Social sciences have discovered that, in blood feuds, both sides blame the other. What I take away from that is that there's something about human nature that, when people get hurt by another, they tend to focus on the fact that the other has hurt them, rather on any prior hurt they did to the other. If you insult someone else, they won't tend to think about anything they might have done that was hurtful or offensive. They'll tend to focus on the fact that you hurt them and lash out. "Punching up" is a sure fire way to perpetuate the problems it purports to solve.
5. "Punching up" is self-righteous and self-righteousness is unvirtuous.
In conclusion, wrong is wrong, period. I can relate to how hard it can be at times to not lash out. I have had my blood boil at the way some really nasty fire-and-brimstone evangelicals have treated me. I've been tempted to be nasty to them. Sometimes, in moments of weakness, I have been, but I regretted it afterwards. I realize that it can be hard sometimes. However, particularly if the individual in question is innocent (but even if they're not), I've found that being self-righteous and cruel to others always backfires.