Debs spoke for a couple hours that day to a gathering of socialist supporters at one of the lowest points for the party. They had been facing a year and a half of persecution by the federal authorities, state authorities, and local vigilante groups, because of their position on the war. Debs was well aware at that point that there were federal agents following him and taking down his every word. There were two stenographers in the audience that day who were capturing what he said.

Debs started the speech by saying, “I’m not going to say everything I’m thinking, but I’m not going to tell you anything that I don’t.” People understood that he was trying to be careful about what he talked about. He gave a standard socialist speech for much of that time, but he did talk about the persecution of his fellow socialists, who were put in jail either for resisting the draft or speaking against the war effort. He said, “If they’re guilty, so am I.”

At a certain point, he made the argument that it’s a rich man’s war and poor man’s fight — that essentially, the capitalists are going to benefit from the war, and workers are the ones who are going to suffer, and that working people never have an opportunity to actually declare war. I think the tipping point was that he suggested to the audience that they needed to know that they were worth more than slavery and cannon fodder.

The government had passed the Espionage Act in 1917, which, in spite of the name, was not used to target spies, but instead used to disrupt those who were opposing the war in various ways. The government’s argument was that the draft was legal and that anybody who was speaking against the war was in a sense encouraging young men to break the law by not participating in the draft.

There was no evidence that Debs actually was trying to do this — the government could find no men in the audience who had not properly registered for the draft — but the way the law was interpreted at that point, it was enough for the jury to suspect evil intentions on the part of a speaker. Debs argued that what really needed to be on trial was the Espionage Act itself, that he was just another citizen who was speaking out on the most important issue of the day, and that he had every right to do so, as did his fellow socialists.

Up to about two thousand socialists, anarchists, Christian pacifists, and other people who just had their own concerns about the war were arrested under the Espionage Act. About 1,200 of them were actually convicted in this period.

When Debs gets a chance to give a speech in Cleveland at his trial, he argues that people were looking back in admiration at abolitionists like Wendell Phillips, but that he was considered a dangerous radical at the time and the free speech rights of the anti-slavery movement were denied. He argued that socialists were just the next wave in the realization of America’s democratic ideals — they were the despised minority that would become the majority at some point.

As soon as the war began, the government created the Committee on Public Information, headed by progressive journalist George Creel. The idea was to claim the loudest voice in the marketplace of ideas by creating the first national mass propaganda campaign. Creel was empowered to hire some of the best writers and artists and filmmakers and theater people to produce a series of propaganda materials.

It was enormously successful. At a point where the United States was very deeply conflicted about going into the war, the transformation was shocking — there was an outbreak of vigilante violence against German immigrants, against anybody suspected of being insufficiently loyal.

So the propaganda campaign was the first piece of this. The flip side of it was the decision to silence dissenting voices. In addition to arresting speakers, the Espionage Act empowered the postmaster to stop the use of the US mail for any publication that seemed to be undermining the war effort. The postmaster, Albert Burleson, a conservative Texan, used this law very extensively and went after the very lively, robust, radical press.

Some editors decided to buckle under that pressure and remain silent, but many more tested the line and ultimately were bankrupted. A lot of the agitators who had made their living writing for the radical press, including Debs, were denied a source of living, and the anti-war movement itself was essentially shut down.

The attorney general basically said, “Look out for your neighbors, and keep an eye out for any suspicious activity, and let us know.” Bogus tips poured in against people who looked like they might not be sufficiently patriotic about the war. This gave sanction to all sorts of local violence.

There were many people who were beaten or humiliated, forced to buy war bonds, and dragged through the streets. There were some lynchings across the country. A minister was kidnapped and beaten and tarred and feathered for making an anti-war speech. Kate Richards O’Hare, one of the most important voices of the Socialist Party at this point, was kidnapped by some vigilantes in North Dakota after one of her speeches.

The physical threats were huge, and Socialist Party headquarters were broken up. It was really impossible for socialists or any other anti-war groups to get together and hold a meeting.

A lot of the political prisoners, as they were called, considered traditional prisoners to be essentially parasites on the body of capitalism. Likewise, many of the traditional prisoners were patriotic and considered these anti-war radicals dangerous. And so there was a real distance between them. But Debs thought about prison as an instrument of class warfare and said, “These people are here because this is one of the tools of capitalist domination,” and felt that this is as much a field where he should be promoting and expressing the values of his political life as anywhere else.

So he ended up very much engaged with the prisoners. People from all over the world were sending him books and candy and tobacco and other gifts, and he would disburse them freely among the prisoners. He spent a lot of time counseling them.

The wardens immediately recognized that he was not the dangerous individual that they’d been led to expect. They befriended him and actually began to talk to him about ways to improve prison life. More than one of them invited him home to have a picnic with the family and remained in touch with him for the rest of their lives.

Debs was in no sense a conventional Christian, but many of these people said that Debs was the most Christlike person they’d ever met.

The war was over, and the Socialists were trying to regroup. Debs had run for president four times already, with a high water mark in 1912 of 6 percent of the vote. The argument that the Socialists wanted to make was that this is a protest vote against what the government had done to the party and the anti-war movement over the course of the war. Nominating Debs was a chance for people to cast their vote on behalf of free speech. Wilson wanted the 1920 election to be a referendum on the League of Nations idea.

The government, I think, took a very confused line on this. On the one hand, Debs was not allowed to speak in any conventional way. He was only allowed to send a press release every other week to the newspapers, though very few of them seemed to run this. At the same time, they let Debs run for president. They let the Socialist Party come to the gates of the Atlanta penitentiary and make a formal nomination.

The party was really divided at this point, smashed by the government, but also increasingly divided over whether the Socialists should join with the Bolsheviks and the Russian Revolution. The party was a diverse coalition of very different sorts of people, and Debs was the unifier, the one person who held it all together. This was his last chance to do that.

That’s right. As I came to study this, I felt like this was one of the great mass social protests in American history that hardly anybody knows about. It certainly was the first mass orchestrated commitment to free speech principles, and in the end, it had a very powerful impact on the development and expansion of free speech rights down to our own time.

Many people did not care that much about the anonymous 1,200 other radicals that were in prison. But something about Eugene Debs being in prison, I think, served as a powerful galvanizing image. Even if you didn’t agree with his politics — and, of course, the majority of the country didn’t — they understood him to be a player in the national conversation. Here he was in prison, running for president. It pushed a lot of people to think about how to push against this.

And so they organized what came to be called the amnesty movement. The Socialists were heavily involved in this, but also the labor unions. Many of the unions were not supportive of Debs’s position on the war and considered the socialists to be interfering with their movement for craft unionism. Samuel Gompers and the American Federation of Labor had a very cooperative relationship with the Wilson administration during the war.

But they began to rethink this when they saw Debs in prison in the postwar period, when there was the Red Scare amid labor unrest. They began to make the connection that, well, if they can put Debs in prison, we might be next.

I think that the most important legacy of the movement was this small group of lawyers, civil libertarians, radicals, and a couple of conservatives who organized what became the American Civil Liberties Union (ACLU). They organized first to protect the rights of the conscientious objectors who had been put in prison for refusing to participate in the draft. Then they moved on to free speech issues for political prisoners.

And that worked. Their arguments about the nature of free speech were developed in this time period and really have continued to shape the way we think about dissent in wartime down to today.

Historians have been arguing about what was going on in Wilson’s head for a hundred years now. Some would suggest that the wartime experience made him more brittle. Certainly he had a stroke in the middle of this, and that seemed to change his personality. A lot of socialists were actually supportive of Wilson’s ideas. The League of Nations idea was something socialists had embraced long before Wilson did. In 1916, he ran for reelection on the slogan, “He kept us out of war.” So it was surprising that he drew a hard line.

Nobody expected Harding to be willing to do this. But that’s just partly a function of the success of the amnesty movement. They had raised the stakes, they had found lots of ways to put pressure on the government, and Harding did not want to inherit that kind of problem. He ran on the idea of a return to normalcy, and having this agitation over political prisoners was something he wanted to put behind him, along with other aspects of the war.

It was not easy for him to do this because he was strongly supported by the American Legion, the Klan was constantly pushing to keep Debs and others in prison, and big business as well. But he did the right thing, and he managed to let Debs out on Christmas morning 1921.

It’s complicated, because I think Debs was heartbroken when he came out of jail to find what had become of his Socialist Party — deeply divided, bankrupted. Many people had lost heart for the cause, and some of the most enthusiastic and committed were urging him to essentially stop believing in the possibility of revolution at the ballot box and join the Bolsheviks.

This was a deeply divisive issue for people on the Left. A lot of his — especially younger — comrades felt like, if the war taught us one thing, it was that the powers that be are never going to let socialism breathe. It’s going to be crushed, by force if necessary. So how can we go back to believing that it’s worthwhile to mount campaigns and participate in the political process when we see what happens when things really get in a crisis moment?

Debs would never claim to be a pacifist, in the sense that violence was never necessary as a matter of self-defense or to advance the cause. But he didn’t see the Bolshevik solution as viable for the American experience. His argument his whole life had been that American workers are in the vast majority. They have the vote. All they have to do is understand how to vote in their own best interests, and socialism will be achieved.

For me, one of the forgotten parts about Debs’s legacy is his willingness to stand and refuse to apologize, refuse to buckle during times of war, and to be the symbol for a commitment to principle that really turned the jailhouse into the moral high ground at that moment. If the country had not had a three-year conversation about the meaning of free speech and had just gone about its business after the war, I think we would not have developed the kinds of commitments to free speech that ultimately came out of the Supreme Court.

I think the experience of vigilante violence, of putting people like Debs in prison, did cause a reconsideration about government overreach during times of war. In the aftermath of the war, several Supreme Court cases led by Oliver Wendell Holmes Jr and Louis Brandeis started to change the definition of free speech, so that the sorts of things Debs did at the Canton picnic would never be considered to be against the law at this point. The government has to prove that speech is about to create an immediate lawless action in order to intervene rather than just making general statements.

Absolutely, that’s right. There are important conversations about why Oliver Wendell Holmes changed his mind, and what the Supreme Court decided and when, and how that has shaped our ideas about free speech. But I don’t think any of that would have happened if it had not been for the wide social protest movement that happened in this period — with Debs serving very much at the center of that conversation.