I believe we are in a new age of hate and fear. I primarily blame Republicans such as Gingrich and McConnell who have fostered an era of denigration and stultification.
BUT:
We have been here before. Nixon was roundly hated. So was LBJ. Reagan was not hated so much, but he did get shot.

Obama got out alive. He did not even get shot. So far, so good. I am willing to grant Trump and his also-rumps the same favor.
What happened at the DC Republican baseball practice was horrible, and although no one but the perp got killed, Scalise was horribly wounded.

We are still deep in the woods.