President Trump — like many Anti-Indian/Wise Use entrepreneurs invested in oil and gas — sees American Indians as in the way of his making money. As a gambling casino owner, he views Native American tribes that have gaming facilities as having an unfair advantage over other Americans.
President Trump thinks reservations should be abolished, which is consistent with his campaign courting white nationalists from the American Freedom Party, and his choice of a Christian supremacist running mate, now Vice President Pence. To my knowledge, Trump is the first US president to be endorsed by the American Nazi Party.
This is not the beginning of difficult times; it is the prelude to civil war.