What's It Like?
A more fitting analogy would be if the UK or France elected a black president. But the fact is, there's no country quite like America, and I don't think anything is really going to be analogous. We did something that's incredible without it being necessarily like other things that may have happened, may happen later, or may never happen at all.
Incidentally, a lot of these comparisons have been made in the context of "America is more racially progressive than Europe because ______." It should be noted, however, that the UK has long since beaten us to electing a leader from an oppressed indigenous ethnic group.