Your ignorance of the respective areas is showing. It's hard to talk about a common culture between California and Louisiana when neither California nor Louisiana has a common internal culture.
In Louisiana, spend some time in Houma, and then some time in Shreveport. Louisiana has a Cajun-dominated region and a region that's very much part of the Old South, and they're not much alike.
In California, spend some time in Berkeley, and then some time in Redding, and then some time in El Centro. California has a relatively liberal coastal culture, a libertarian culture in its interior, and an almost exclusively Hispanic culture in portions of its south.
I'll gladly agree that Europe is gloriously diverse, but you really should stop underestimating American cultural diversity.
In Louisiana, spend some time in Houma, and then some time in Shreveport. Louisiana has a Cajun-dominated region and a region that's very much part of the Old South, and they're not much alike.
In California, spend some time in Berkeley, and then some time in Redding, and then some time in El Centro. California has a relatively liberal coastal culture, a libertarian culture in its interior, and an almost exclusively Hispanic culture in portions of its south.
I'll gladly agree that Europe is gloriously diverse, but you really should stop underestimating American cultural diversity.