Monday's fracas was a symptom of a growing malaise in British politics, according to Rob Ford, professor of political science at the University of Manchester.
It followed street scuffles during Scotland's independence referendum in 2014 and activists draping a banner from a bridge in Manchester during the Conservative Party's annual conference in 2017 saying "Hang the Tories".
"I think Brexit certainly deepened it ... this trend towards intensifying distrust of politics and politicians, representative institutions, the media," Ford said. "That distrust has now become much more visible because it is now becoming a serious obstacle to addressing complex issues."
Politicians on all sides of the Brexit debate had encouraged this kind of thinking, Ford said, adding: "I fear that the beast that they have unleashed has now turned on all of them."