To be fair to the donald, has it ever been any different?
The problem is he emboldens these people with his rhetoric. If he uses the same language about foreigners and people of different skin colour (not orange obv), then it all becomes normalised. He also praises the most extreme commentators on Fox news and, other than Nadine Dorries and Esther McVey*, can you imagine any members of Government retweeting Katie Hopkins or Tommy Robinson?
Sure this fella may have shot up Walmart without Trump, but he must be responsible for some of the increase in these hate attacks? Dare say you may have a point on gun control given history and the numbers of members of congress and the senate bought out by the NRA.
* and maybe Boris after a few beers?