I agree with everything you said there! That last sentence is a stretch. But, not too much.
Unfortunately, a lot of the people who are now heavily invested in supporting him have no line that is too far for him to cross and they will always look for blame to be placed anywhere and everywhere else but on him.
When you hear clips of his supporters, and their disgusting vitriol for certain groups, it becomes less of a stretch. The rhetoric about their country being stolen really resonates with them. When you become convinced that your country is under attack, violence begins to look more like a justified response. Not for everyone. But for someone crazy enough to cover their van in trump stickers and democrats in crosshairs...