The northern mind is a funny thing. Your “laughing” points out the incredible difference between our cultures.
Both cultures understand that there was segregation in the South...so it goes unsaid. Southerners have to point out that northerners were, and still are, segregationists, even as they pretend that it happens naturally. (And even as they pretend to hold some sort of moral high ground in the matter.) Meanwhile, people in the South live in mixed neighborhoods and have largely dealt with the its segregationist past.
Pointing out that there is segregation in the north is not funny, it is a necessity in such discussions. Laughing “when a Southerner ‘accuses’ the north of practicing segregation” demonstrates profoundly demonstrates the false position you have constructed so as to wrongly look down upon Southerners.
The Union, as it stands today, is very uncomfortable and unnatural. I guess it might be cultural also....
I don't deny that there's de facto segregation in the north. There's de facto segregation in pretty much every city in the US. But if you're going to deny that there are predominately black neighborhoods in the south, you're delusional.
Laughing when a Southerner accuses the north of practicing segregation demonstrates profoundly demonstrates the false position you have constructed so as to wrongly look down upon Southerners.
Just because it's funny that someone in a glass house starts throwing stones, it doesn't mean the other person doesn't live in a glass house, too. But I'll pick the historical record of my glass house over yours.