What does the moral Left act like the depraved?

Why is the Left so abusive? Why do activists claiming a superior morality in fact use hate-speech and profanities?

Todd Sampson on the ABC last night:

Refugee activists yesterday:

A protester, yelling obscenities, stormed the stage and forced the Prime Minister to stop speaking during his major economic address in Melbourne.

The woman — holding a sign that read “FFS close the bloody camps” — made it within metres of Malcolm Turnbull.

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