I've written about this extensively on this forum. I don't call it "white" guilt, but close..I call it "Western guilt". It's found in western societies, those based on a protestant Christian culture, which has now moved generally BEYOND that into what might be called a 'secular, post-Christian" society..sound familiar? Right...The US, Canada, some of Western Europe, ...Australia , NZ....but not many other places. Note that not ALL 'white" societies are included...Catholic countries, for example, are largely immune. Curiously, Scandinavia, which hasn't done anything "mean" to anyone for centuries, seems to suffer from 'white guilt'. Why? Don't know...
This "guilt" (white or whatever) is what "makes" us....for example, argue about the 'rights' of illegals...or the 'atrocities' that "we" (ALL of us, apparently), have committed in the past..or our "responsibility" for fomenting troubles and strife over most of the world..even for "colonialism"...which, ironically, the US didn't even DO, for the most part. The British were certainly 'colonizers', and today suffer much 'white guilt'. Yet the Spanish and French were HUGE colonizers...but seem largely immune from this guilt.
What makes this "white" guilt special, and worth discussing for its seeming bizarre contradictions, is that MOST huge nations have all sorts of atrocities to their credit. Russia, for example, brutally killed uncounted MILLIONS of peasants in its ruthless and bloody history---FAR in excess of anything the US did. China did the same. Japan's human-rights record in WWII was truly abominable. Yet these places have no sense of collective guilt in their societies. Muslim nations, for all their ruthless history, seem totally oblivious to any sense of guilt borne as a society.
Mexico has "screwed" its own poor for so many generations it's simply taken for granted...it's treated as a tired 'joke'.... Yet the US feels "guilty" for the plight of today's Mexican illegals, while Mexico feels none whatsoever. Though fully ten percent of Mexico has now LEFT the country, for the US, the 'common wisdom' is that any mistreatment suffered by these folks is due to "our" unkindness. Mexico gets a 'pass'..in fact, Mexico actually criticizes us quite regularly...for mistreating the people who "it" forced to leave....the hypocrisy is breathtaking. But it works, when one society feels guilt, while the other doers not.
Africa? Whole different story. Blame and guilt are directed at the Euopean colonizers and their 'excesses'...yet no 'guilt' at all seems to be associated with the continuing bloodbath that is 'business as usual' in Darfur, Rwanda, Sierra Leone, etc etc etc., right up to the present day. Lots of atrocities, lots of anger, lots of 'charges' being thrown around....but no 'guilt' at all.
Hope this answers your question. Not so much a "white" phenomena as it is a "secular, protestant-based" one. Why?....I don't know.
By the way' "white guilt" also prevents us from COMPARING ourselves with other, worse, far more brutal places. White guilt says, in esence, that "the tyrants and dictators and violent thugs in THOSE places aren't responsible for their behavior. It's their culture, it's the way they live, and they don't know any better. WE DO, and we're guilty." Thopse nations which experience "white guilt", by the way, are ALSO the same societies bent on adopting "multiculturalism"....as if to say "other cultures are just as good as OURS, and a whole lot morte interesting, as well". MOST of the world, of course, has ZERO interest in multiculturalism. THey figure their culture is the "best" one for them, period....therefore, no self-doubt, no multiculturalism, no 'guilt'.
"White guilt" in my opinion, contains just a HINT of racial superiority..."we" are better than "them", and therefore we should show it, by acting better. Yet at the same time, we're GUILTY, and "they" aren't....because they "can't HELP it"....
BTW..I'm white, but not protestant. My wife's neither white OR protestant. But we both "see" this. Personally, I seem just a touch guiltier than HER, in regards to the damage "I've" done around the world....(??)hmmm