Debs ran twice for president against the man who put the "Teddy" in "Teddy Bear," in 1904 and again in 1912 when Roosevelt ran on the Bull Moose Party ticket. (Good party name or best party name?)
In most ways, the two men are a study in opposites: Debs was from humble beginnings and Roosevelt from the lap of luxury. Roosevelt was very well educated and Debs was a high school dropout. Debs emphasized what an everyman he was ("not one bit better than the meanest on earth" (1)) whereas Theodore Roosevelt was one of history's greatest egomaniacs. (Roosevelt's own daughter said that he "wanted to be the bride at every wedding and the corpse at every funeral.")
And this juxtaposition continues.
Debs was a pacifist and Roosevelt was a war hawk to the max. While Debs was talking about why workers should refuse to be cannon fodder, Roosevelt was leading preparedness rallies, drilling soldiers, and trying to enlist, even though he was way too old. Roosevelt believed that war made men masculine and was super proud to be remembered as the hero of the Spanish American War. Roosevelt insisted that all of his four sons volunteer for World War I service; his favorite son, Quentin, was killed in battle.
On the other hand, Roosevelt supported a bunch of the labor reforms that Debs was calling for. His Square Deal platform emphasized better conditions for workers, and President Roosevelt several times intervened on the side of labor during strikes.
In fact, during the campaign of 1912 when Roosevelt broke with the Republican nominee, Taft, and ran as an independent, his platform so much mirrored things that Debs was saying that a cartoonist created a cartoon accusing Roosevelt of stealing Debs' clothes.
Guess it's true: opposites do attract.
Probably the most famous Socialist in America during the early 20th century—besides Debs himself—was the writer Upton Sinclair.
Sinclair's novel, The Jungle, dealt with the lives of meat-packing workers and the disgusting conditions under which they worked. The Jungle created a national sensation, but not for the reasons Sinclair intended—he hoped his readers would so identify with the novel's hero, who becomes a Socialist, that they would be converted to Socialist philosophy.
Instead, readers focused on the unsanitary working conditions and revolting, unhygienic quality of American meat. The book led to a huge public outcry, very immediate reforms, an invitation to the White House to discuss meat matters with President Roosevelt, and the creation of USDA standards. As Sinclair wryly noted about his book,
I aimed for their [readers] hearts and hit their stomachs. (Source)
But whatever his plan, the popularity of The Jungle made Upton Sinclair a major voice for American Socialism.
Upton and Eugene (yes; we're on a first name basis with these guys) saw the world a wee bit differently, however. When WWI began and, even more, when America entered the war, Sinclair saw the Germans as a serious threat to America and believed America should join the Allies.
He advocated an idea he called "democratic defense" and thought that the government should take over all munitions factories and run them on Socialist lines. And he thought that a universal draft could lead to solidarity among soldiers, a Socialist ideal.
Basically, Sinclair didn't see the war as just a capitalist war about markets and he believed that the Socialists should support the government. He wrote to Debs and tried to convince him about this idea of defending democracy, but Debs wasn't buying it, feeling that the United States was acting far from democratically as it pursued its path to war.
Though Sinclair would ultimately resign from the Socialist party over this split, he still worked diligently to try to win Debs' freedom when he was imprisoned under the Espionage Act.
A fact you probably know: in 1967, twenty-five-year-old Muhammad Ali was the heavyweight champion of the world. And he was also the heavyweight champion of trash-talking.
At the peak of his fame and athletic prowess, he received a draft notice telling him to report to his local draft board. Ali opposed the Vietnam War and refused to fight in it, releasing a statement that said:
It is in the light of my consciousness as a Muslim minister and my own personal convictions that I take my stand in rejecting the call to be inducted. I do so with the full realization of its implications. I have searched my conscience. (Source)
And Ali—like Debs—was put on trial for draft evasion and convicted.
Though Ali was allowed his freedom during his long fight against this conviction, the World Boxing Association suspended him and for five years he wasn't allowed to fight. So, like Debs, Ali protested against a war he thought was unjust at a great personal cost. For an athlete, losing five years of competition during the peak athletic years stands as a sincere personal sacrifice.
The leader of Russia's Bolshevik Revolution, Lenin was the world's most famous Socialist while Debs was opposing World War I and going to jail for his speeches that urged workers to see the war as a capitalist ploy.
For his part, Lenin fiercely opposed Russia's involvement in the war and took Russia out of the action as soon as he solidified his power. Debs was super-hopeful, at first, about the Russian Revolution creating a real workers' paradise, and for many months his thinking about America's workers was influenced by the events in Russia. During this time, he at first tried to develop an American Socialist policy that would be supportive of Russia's revolution.
Lenin said nice things about Debs and vice versa—at first. When all of his Socialist buddies were telling Debs how great he was for being willing to go to jail, Debs himself said that his deeds were "almost contemptible" when compared to Lenin.
Back at him, Lenin called Debs "a fearless man…a true representative of the revolutionary proletariat" (source).
But while he was in prison, Debs leaned about some of the harsh things that Lenin and his Bolsheviks were doing to their political opponents in Russia. He was horrified when the czar and his family were murdered and sent a telegram to Lenin in 1922 protesting more murders of political enemies.
Debs continued to praise the ideal of creating a workers' republic, but what Debs was envisioning was democratic, not authoritarian. He and Lenin saw Socialism taking very different paths.