Uh oh, is this a reference to the radar meme/study?
The one that conservatives keep claiming shows that liberals care more about out-groups than in-groups, but actually shows that either 1) many conservatives are illiterate and can't read a survey question, or 2) many conservatives literally don't care if right or wrong happens to acquaintances, strangers, their countrymen, humans in other countries, non-human animals, living things, etc?
Well it's not really a meme, it's a study. And it was an earnest question as to whether GP was referencing the study. They claim they weren't ¯\_(ツ)_/¯
Also it sounds like you're referring to the British political parties Liberals and Conservatives, not the lowercase-l and lowercase-c political philosophies by the same names, which the study is actually about.
> Oppression would be quite impossible throughout history if people weren't willing to oppress their own kind to the benefit of others.
No what's far more common is that people change their perception (or have different perceptions) of who is "their own kind."
You can actually see this happening in real time in the US with the emerging concept of "Heritage Americans." It's a way for losers and crybabies to narrow the scope of who is "their own kind" without having to openly declare that they simply don't love their countrymen.
My impression is that the foreign/out group delegate the actual oppressing to local representatives, who are more than eager to do it towards their own kind.
It's complex. My wife's father-in-law immigrated from Italy to escape the destruction wrought by fascism in WWII and seek economic opportunity. He was part of a diaspora of a small village in Abbruzze that settled around Binghamton, NY. I would say that they all love Italy and they all love the U.S.
Those are people I know very well because I have been to so many parties, dinners, and other events with them. I've seen the same thing with people from India, China, Sri Lanka, etc. I'd assume that it's the normal condition of immigrants.