I have vague memories of my mother thinking Mexico was dirty. (Don't get me going about my aunt and the japanese.) They both were troubled by Protestants..
What I am getting at is that at least in southern california in the forties and fifties, there was this whole "they're not like us" thing, xenophobia on parade. Strange in that my mother's family came to Los Angeles around 1920 - they were the newcomers. I saw that kind of attitude change in multiplying individual cases with people getting to know people. That whole xenophobia thing seems to have somewhat broken down, but then I'm not living in pockets of real ethnic hatred or even distaste.
I am picking up that here in New Mexico many people are proud of being descendants of early Spanish settlers, and not Mexican.
My own biggest pickle is capitalization. I'd rather not capitalize any country or state or origination but I knuckle under and do it sometimes, making me appear very confused.