A little under a month ago, Tucker Carlson dedicated a segment of his show to violence conducted by the political left. He clearly reveals how the left is now using violence and threats of it as a political tool.
Environmentalists use violence constantly to achieve their aims. More recently, animal rights groups would stalk, threaten or even assault people involved in medical research that involves using animals. Like has been pointed out before, in any system of government where leaders are chosen, the loser must concede peacefully and allow the winners to govern. If not, then a society based on a government that elects its leaders is meaningless and political parties become nothing more than armed militias.