Sanders has spent his entire adult life preaching the benefits of socialism. To describe Bernie Sanders as a Marxist, communist or socialist is far more accurate than the dark descriptors employed to sum up Donald Trump.
In the past 100 years, it is estimated that communist states killed as many as 100 million people. It began, practically with the Bolshevik Revolution and the dark rise of the Soviet Union.
Central planners rely on conformity at any cost and that historically looks a lot worse than any Donald Trump tweet imaginable.