It's actually the academic term for American Indians.
You're speaking to an American cultural anthropologist, and I say you're full of shit on that point. There's no standard "academic term for American Indians" though both "American Indian" and "Native American" are much more common in the US than "Amerindian", which is mostly used by overseas art collectors and museum curators in Europe.
Firstly because no one calls themselves that, and secondly it's a slangish slopping together of two completely inaccurate terms.
But many people (not me, I realized Kamala Harris was the lesser of two evils) voted for Trump because they were frustrated by Biden's penchant to slide to the left on a variety of issues.
How is it even a "Leftist issue"? The situation resembled Waco in most respects except the race of the targeted arrestees and the chain-of-evidence issues that emerged during and after the trial. If you think the right to bear arms should not be infringed, self-defense never questioned, etc etc you should be swinging in Peltier's defense, not bitching about the conditions of his hospice care.