Recent disruptive protests — from diners at Mexican restaurants in the capital calling the White House adviser Stephen Miller a fascist to protesters in Pittsburgh blocking rush-hour traffic after a police shooting of an unarmed teen — have provoked bipartisan alarm. The CNN commentator David Gergen compared the anti-Trump resistance unfavorably to 1960s protests, saying, “The antiwar movement in Vietnam, the civil rights movement in the ’60s and early ’70s, both of those were more civil in tone — even the antiwar movement was more civil in tone, but certainly the civil rights movement, among the people who were protesting.”

But those who say that the civil rights movement prevailed because of civil dialogue misunderstand protest and political change.

This misunderstanding is widespread. Democratic leaders have lashed out at an epidemic of uncivil behavior in their own ranks. Senator Charles Schumer described the “harassment of political opponents” as “not American.” His alternative: polite debate. “If you disagree with someone or something, stand up, make your voice heard, explain why you think they’re wrong and why you’re right.” Democrat Cory Booker joined the chorus. “We’ve got to get to a point in our country where we can talk to each other, where we are all seeking a more beloved community. And some of those tactics that people are advocating for, to me, don’t reflect that spirit.”

The theme: We need a little more love, a little more Martin Luther King, a dollop of Gandhi. Be polite, be civil, present arguments thoughtfully and reasonably. Appeal to people’s better angels. Take the moral high ground above Trump and his supporters’ low road. Above all, don’t disrupt.

This sugarcoating of protest has a long history. During the last major skirmish in the civility wars two decades ago, when President Bill Clinton held a national conversation about race to dampen tempers about welfare reform, affirmative action and a controversial crime bill, the Yale law professor Stephen Carter argued that King “understood that uncivil dialogue serves no democratic function.” ...