I have the impression most Injuns are pretty chill. Went to a Redskins game a few years back and of course Fake News was all over the name controversy. Said the natives planned a big protest, but when we walked around the stadium the only protest we saw was a four guys holding a sign and getting interviewed by local news crew, which from the looks of it actually outnumbered them.
I'm sure they'll have a sizeable rent-a-mob at Rushmore tonight, but don't believe for one second it constitutes a majority of native american thought, or even the Sioux for that matter.