Krauthammer’s columns were worthwhile reading for people of any political persuasion.
Krauthammer had the courage and integrity to call Trump’s comments on Charlottesville “a moral disgrace,” to concede that Don Jr.’s emails constitute evidence of “collusion,” to criticize Trump’s coolness to NATO, and to cheer when “constitutional guardrails” contain Trump’s indifference to the rule of law and other basic American values.
The tweets you cite are indeed hateful. Increasing political polarization and mutual contempt are grave concerns, but I doubt trolls on the left are more numerous or vicious than trolls on the right — even when you subtract the Russian imposters. It would not be hard to find similarly juvenile & mean-spirited conservative tweets. Consider, for example: