Which was mostly done by the British, French, Spanish, Dutch, and Russians (Alaska) before the US became a country. Yes, the genocide of the Native Americans was an atrocity, but 90% of it happened within 100 years after Columbus arrived. Even so there was no 5 year period in the US to be that came close to as many deaths as the the years of the Russian Civil War.
Which was mostly done by the British, French, Spanish, Dutch, and Russians (Alaska) before the US became a country. Yes, the genocide of the Native Americans was an atrocity, but 90% of it happened within 100 years after Columbus arrived. Even so there was no 5 year period in the US to be that came close to as many deaths as the the years of the Russian Civil War.