Being kind and giving extra resources to those with disabilities, and to some degree even those of lower status. In theory, pure evolution should operate selfishly (more for me less for you) most of the time and even a more complex evolutionary pressure that seeks the benefit of the species vs the individual. There’s no benefit to caring for and giving resources to those who can’t or objectively (again, to from a pure genetics perspective l shouldn’t be allowed to breed. But morally, as a society, we care extra for them, not less. Anyone who wants to be rid of or take from those unfortunates are (rightly) considered sociopaths.
I live in Nashville (and my sister lives in Germany). You should be fine. It’s a great place to visit.
Any place in the world has the small chance of a drunken idiot making a fool of themselves by revealing themselves to be racist. We’re no different. But you’re not going to be harassed by police officers or anything like that (unless you’re doing something worthy of their attention anyway).
The only places where I’d be the slightest bit concerned would be in the small town rural areas between Nashville and the national park. Even then you should be fine, but the odds of running into a racist idiot will go up from like 1% to 3%. And even if you do, it’s not like you’ll be in danger. They’ll just do their best to make you uncomfortable by saying something nasty. They won’t refuse you service or anything crazy like that.
Honestly, even in those areas you’re likely to be looked at suspiciously because of your foreign accent more than the color of your skin.