Reason magazine has a very good Nick Gillespie interview of former ACLU head Ira Glasser.  (The bolded question is Gillespie, the rest is Glasser):

It wasn’t until my 30s that I began to understand free speech, that the real antagonist of speech is power. The only important question about a speech restriction is not who is being restricted but who gets to decide who is being restricted—if it’s going to be decided by Joe McCarthy, Richard Nixon, Rudy Giuliani, [President Donald] Trump, or [Attorney General] William Barr, most social justice advocates are going to be on the short end of that decision. I used to say to black students in the ’90s who wanted to have speech codes on college campuses that if [such codes] had been in effect in the ’60s, Malcolm X or Eldridge Cleaver would have been their most frequent victim, not David Duke.

Was that a convincing argument?

It pulled people up short. They imagined themselves as controlling who the codes would be used against. I would tell them that speech restrictions are like poison gas. It seems like it’s a great weapon to have when you’ve got the poison gas in your hands and a target in sight, but the wind has a way of shifting—especially politically—and suddenly that poison gas is being blown back on you.

Back when I was at the University of Chicago, there was a great deal of controversy about the ACLU’s decision to defend the right of Nazis to protest in Skokie, Illinois (which had a large Jewish population.)  In 1977, there were many Holocaust survivors in Skokie, so the ACLU’s decision was understandably highly controversial.    Thus I was interested to discover that the strategy seems to have paid off:

How did Skokie turn out?

We won the case at every level. It even went up to the Supreme Court. It was an easy case legally because these bonding statutes had been struck down a million times before.

Meanwhile, some of the people who lived in Skokie—once we won the case and the Nazis said they were coming—did what the town should’ve advised them to do in the first place: They organized a massive counter-demonstration. About 60,000 people were ready to come. And then the irony of ironies is, when confronted with that, Collin and the neo-Nazis never came to Skokie. Once we won that case, it also allowed them to demonstrate in Marquette Park, which was what they had wanted to do all along. They also confronted a massive counter-demonstration there that never would have happened without the case. It completely overwhelmed them; they couldn’t be seen or heard. Right after that they fell apart.

One thing I’ve discovered in life is that bullies tend to be cowards.