Sanders' speech, coming two weeks before the first debates of the Democratic primary, is his most aggressive attempt yet to reframe the conversation about his political views. His ability to define the debate around his core political philosophy will be crucial if he is to convince voters that his embrace of democratic socialism isn't a barrier to winning the White House.
"Let me be clear: I do understand that I and other progressives will face massive attacks from those who attempt to use the word 'socialism' as a slur," Sanders said. "But I should also tell you that I have faced and overcome these attacks for decades, and I am not the only one."
Sanders, an independent senator from Vermont, made a similar attempt in 2015 to explain the views that have shaped his ideology but have also become a significant political vulnerability.
But this year, the speech comes in a reshaped political environment, where Sanders is no longer the sole progressive taking on an establishment candidate as he was in the 2016 primary when he ran against Hillary Clinton. He's now one of two dozen Democratic White House hopefuls, several of whom are also unabashed liberals, like Massachusetts Sen. Elizabeth Warren, who has been rising in the field.
And they're operating in an environment dominated by President Donald Trump, who has called Sanders "crazy" and seized on some of the proposals that he and other Democrats are running on and portrayed them as outside the mainstream of most Americans' views.
During Wednesday's speech at George Washington University, Sanders said Trump "believes in corporate socialism for the rich and powerful," while he believes in "a democratic socialism that works for the working families of this country."
Sanders is fond of noting that many of his Democratic rivals now back policies he has championed, such as "Medicare for All," that were seen as too costly and too liberal in previous elections. But few of the other Democrats seeking the White House share his support for democratic socialism.
Former Vice President Joe Biden, who has jumped to the top of the Democratic field in part because of a perception that he's the most electable candidate in the race, has derided the notion that politicians must be socialists to prove they're progressive. Other liberal candidates, including Warren and Sen. Kamala Harris of California, have noted that while they have problems with the economic system, they remain capitalists.
And Colorado Gov. John Hickenlooper, who is also seeking the Democratic presidential nomination, plans to give a speech Thursday that his campaign is marketing as a rebuttal of Sanders.
Trump and his allies have, nonetheless, warned against the threat of socialism if a Democrat gets elected to the White House.
When Sanders entered the 2020 race in February, a spokeswoman for Trump's campaign said Sanders had "already won the debate in the Democrat primary because every candidate is embracing his brand of socialism" and said Trump is the only candidate who will keep the country "free, prosperous and safe."
On Tuesday in Iowa, Trump claimed Democrats will "destroy this country" and turn the U.S. into "another Venezuela."
"Don't let it happen to us," Trump warned at an Iowa GOP dinner in West Des Moines.
Sanders last spoke in depth about democratic socialism in November 2015. In that speech, which was also held in Washington, Sanders similarly invoked the legacies of President Franklin D. Roosevelt and the Rev. Dr. Martin Luther King Jr., arguing that democratic socialism was reflected in their priorities.
This year, he made the case that popular programs like the New Deal, Social Security and Medicare had been, at times, labeled by opponents as socialist.
He quoted former President Harry Truman, who in 1952 said, "Socialism is the epithet they have hurled at every advance the people have made in the last 20 years."
And as he did in his first presidential run, much of Sanders' campaign speech was focused on promising a wholesale revolution, including a fundamental rethinking of the political system. Asked in a telephone interview on Tuesday how he would tangibly change Washington's centers of political power to make his visions a reality, he said he would do so "by taking politics out of Washington."
"What the political revolution means to me, above and beyond democratic socialism, is getting millions of people who have given up on the political process, working people and young people, to stand up and fight for their rights. So those are the profound changes that we will be bringing about," he said.
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