Another interesting way to look at this is to look at what level of income equality people are advocating for, on a macro scale.

Most people making arguments against income inequality in the US seem to want income to be more equal down to and including themselves, but never very far below themselves. They want it to be equal within the US, but I have a hard time believing they'd be as excited to extend that same income equality worldwide. Doing so would see even the poorest Americans taking a massive cut in lifestyle and living at a level of poverty most people in this country have never seen or experienced.