So aside from the classic (if done to death) Rome-wank, the idea of a United States spanning across all of the Americas is easily one of my all-time favorite AH concepts. I find it fascinating to ponder how such a state would come into being, and how it would influence the world around it. Your challenge is as follows: With a POD of anywhere from the dawn of time to 1900, the US (or an entity similar to the US, with my main stipulation that it be initially English-speaking) must have complete ownership of the entirety of both North and South America by the modern day. The US must be democratic in nature, with all peoples and states having equal representation in the government (so no "fascist America goes on a conquering spree"). With a POD of literally whenever, is this even remotely possible? And if it is, how would such a state even function? I imagine that the government would work far differently than the government of OTL US. The US would undoubtedly have to solve its issues with racial and religious intolerance for this to work. I truly hope that there is a way for such a state to come into being without turning into a dystopic nightmare. I absolutely love the idea of a multicultural pan-American hyperpower serving as a shining beacon of liberty and democracy.