There's a really amazing post here about outgroups and the distorted way we reason --- or fail to reason --- about them. It's a bit long, but totally worth the read.
http://slatestarcodex.com/2014/09/30/i-can-tolerate-anything...
https://en.wikipedia.org/wiki/Ingroups_and_outgroups
"In sociology and social psychology, an ingroup is a social group to which a person psychologically identifies as being a member. By contrast, an outgroup is a social group with which an individual does not identify."
https://en.wikipedia.org/wiki/Social_identity_theory
"A social identity is the portion of an individual's self-concept derived from perceived membership in a relevant social group.[1] As originally formulated by Henri Tajfel and John Turner in the 1970s and the 1980s,[2] social identity theory introduced the concept of a social identity as a way in which to explain intergroup behaviour.[3][4][5]"
Still, individuals do change their ingroup membership and can remain as intolerant to then fully new outgroup. It would be good to have a name for this phenomenon: being intolerant to whatever person's current outgroup is. And there is one, which happens to have more uses than only this:
https://en.wikipedia.org/wiki/Prejudice
"The word is often used to refer to preconceived, usually unfavorable, judgments toward people or a person because of gender, political opinion, social class, age, disability, religion, sexuality, race/ethnicity, language, nationality, or other personal characteristics. In this case, it refers to a positive or negative evaluation of another person based on their perceived group membership.[1]"
You have just described at least half of the dozens of posts on that blog.
(There's a best-of list, still intimidatingly long, here: http://lesswrong.com/r/discussion/lw/mmg/yvains_most_importa... and a best-of-best-of subset of that, unfortunately with only the titles and no links, here: http://lesswrong.com/r/discussion/lw/mmg/yvains_most_importa.... I haven't looked through either of those lists and make no claim that they have successfully selected the best. The lists include not only posts on Slate Star Codex, but also others -- mostly earlier -- from the same author elsewhere.)
This is something I've never seen stated outright before, and it seems totally true to me.
(For the avoidance of doubt, my comment that what you said applies to lots of things on SSC wasn't intended as any sort of criticism -- I wasn't saying "boo, you failed to describe the article in a way that distinguishes it from the others" but "yay, SSC has a lot of really good articles".)
Only you: freedom fighter, liberator
Only they: imperialists
Only you: protector
Only they: baby killers
Only you: collateral damage
I'm sure George Carlin could come up with more expensive shots… Man, I miss him.
"Every faction in Africa calls themselves by these noble names - Liberation this, Patriotic that, Democratic Republic of something-or-other... I guess they can't own up to what they usually are: the Federation of Worse Oppressors Than the Last Bunch of Oppressors. Often, the most barbaric atrocities occur when both combatants proclaim themselves Freedom Fighters."
Interestingly, some people discussing the leak show emotional and "religiously righteous" response to the people who possibly made or even just considered an act of "infidelity" (not to be confused with the "infidels.")
Infidel: "Late 15th century: from French infidèle or Latin infidelis, from in- 'not' + fidelis 'faithful' (from fides 'faith', related to fidere 'to trust'). The word originally denoted a person of a religion other than one's own, specifically a Muslim (to a Christian), a Christian (to a Muslim), or a Gentile (to a Jew)."
C.f. Barbarian, 2: "2. Hist. a. One not a Greek. b. One living outside the pale of the Roman empire and its civilization, applied especially to the northern nations that overthrew them. c. One outside the pale of Christian civilization. d. With the Italians of the Renascence: One of a nation outside of Italy."
Kinda along similar lines: expats vs. immigrants.
"Oh no, Paul and Iza are expats. Not at all like those job-stealing immigrants who moved in next door..."
(aside: does wrong fit your original question?)
> In common usage, [expatriate] is often used in the context of professionals or skilled workers sent abroad by their companies.
A Guardian writer disagrees, saying "expat" means "white immigrant":
http://www.theguardian.com/global-development-professionals-...
Personally, I think "expat" is used more in the sense of an (usually white) immigrant from a richer country to a poorer country. EG, an Indian recruited to work at Google in San Francisco would be an expat by your definition but I think most people would use the term "immigrant." Conversely, I'd expect the term "expat" to be used for an American white guy who was travelling the world after getting laid off, impulsively decided to stay in Bangkok, and now does freelance web design, lives in a nice neighborhood, and hangs out mostly with Americans and Europeans.
I am not saying I think this is how the term should be used, just describing my experience with it.
Also, one deeper, to my ear, 'expat' has a flavour of intending to return, where immigration generally sounds more one-way and permanent - which of course again parallels the 'rich' narrative: it's much easier to intend to return to your rich country of origin than it is to return to a poor one.
People who "emigrate" from the UK primarily seem to go to Australia, by that I mean that's how the word is used. A high-school friend went to "work in the States" rather than "emigrating to America", for example.
Migrant (emigrant/immigrant) seems to be used primarily for those under some duress of compulsion, eg threat of violence or need of work that is otherwise unavailable.