"It Is Getting Harder and Harder to Distinguish the 'Normal' Elements of Conservatism from the 'Kook' Parts"

"The left certainly has illiberal, paranoid modes of thought. The difference is that the left-wing version resides outside the boundaries of two-party politics, because the Democratic Party is fundamentally liberal not radical. Coulter's examples of 'liberal' violence inadvertently bear this out: the Haymarket Square bombers were anarchists, and the Unabomber developed an idiosyncratic hatred of technology that did not connect to other nodes of left-wing politics. The street-fighting cult antifa lies outside of, and is primarily hostile to, Democratic politics. Left-wing violence from the 1960s likewise came out of radical groups who viewed the Democratic Party with contempt.
"The Republican Party, on the other hand, has followed a course that has made its rhetoric amenable to extremism."

Jonathan Chait at New York argues that "Trump's party is a petri dish for diseased minds."