The thousands of nuclear weapons we have make this an academic question. Everyone knows that we would use them if facing an invasion of our homeland, so there never will be a foreign invasion on our soil.
I know we've done some shitty things to a variety of different countries over the years, but those acts are never going to be reciprocated in kind because they're the kinds of acts that only the powerful can do to the weak, and the US is not weak. It's not a value or moral judgment, it's just the reality of how power and force work.
