Oh my!
The "Left" that now created this mess, are trying to pin it all on the Donald.
It is no more Mr. Trump's fault, than it is Barack Obama's (or Bill Clinton, or, or, or...) fault. And, yes, it is all their "faults". What we are seeing is the cracks coming through in the veneer of race-relations that so many earlier Governments "papered-over" but never  fundamentally addressed.
To get at the basis of "man's-distrust-of-his-fellow-man" you need to go a lot deeper and broader than any Government has done in the US (and most other places in the world). Don't believe me? Look at the ethnic tensions in both Asia and Europe.
The US Democrats would have likely done a better job at keeping the lid on this pressure cooker, but they chose to squeeze out Bernie Saunders, the only candidate they had that could bridge the divide, in favour of Hillary who proved she couldn't unite the country on anything. So blame the Dems for Trump, they got what they brought on themselves. Not pretty for sure.