Bernie Sanders addressed Brooklyn College's Commencement at Barclays Center on May 30, 2017. View Full Caption Facebook/Brooklyn College

FORT GREENE — Vermont Sen. Bernie Sanders returned to his home borough of Brooklyn Tuesday to deliver Brooklyn College’s commencement speech, entering the stage to rousing chants of "Bernie."

Though he never mentioned President Trump by name, Sanders decried the current administration — which he called an “oligarchy” set on stripping 23 million people of their health care coverage, decimating Medicaid, de-funding Planned Parenthood and laying waste to supportive resources like food stamps, afterschool programs and Pell grants to help middle class families pay for college.

He called on the more than 4,100 undergraduate and graduate students getting their diplomas inside the Barclays Center alongside him to put all their efforts into turning the nation in the right direction.

“My message to you is very simple: think big, not small, and help us create the nation that we all know we can become,” he said.

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The Independent senator, who was born and raised in Brooklyn and attended Midwood’s P.S. 197, Sheepshead Bay’s James Madison High School and Brooklyn College in 1959, which he attended briefly before transferring to the University of Chicago, was awarded a Doctor of Humane Letters degree for his “groundbreaking career in politics, visionary approach to public policy and higher education, dedication to civic welfare and commitment to equality.”

Sanders left Brooklyn College, he said, because his mother passed away the previous year and he felt it was time to “leave the neighborhood and see what the rest of the world looked like.”

But he told graduates that his childhood in a 3.5-room rent controlled apartment with his parents and older brother was formative, adding that he never forgot the financial pressures that caused friction in his household.

By comparison, he said, today's administration in the White House, “They have the chutzpah to provide $300 billion in tax breaks to the top 1 percent.”

He also complained about the deniers of climate change helping the fossil fuel industry and the “broken” criminal justice system that imprisons more people than other countries.

Though some graduates might prefer not to get involved because the “system is rigged,” Sanders told them, “You do not have the moral right to turn your back on saving the planet,” saying the only “rational right” was to “stand up, fight back and reclaim democracy.”

He also recounted how his father fled Poland because of anti-Semitism when he was 17, and how for his family issues like racism, right-wing extremism and nationalism were not political issues.“They were issues of life and death.”

As a “kid growing up in Brooklyn,” he never would have imagined the U.S. could grow into the unequal society he sees today where “the top one-tenth of the 1 percent owns almost as much wealth as the bottom 90 percent.”

Brooklyn College President Michelle Anderson introduced Sanders recalling how the senator’s grassroots activism — that was literally about a patch of grass — began at the Flatbush campus. The young Sanders penned a letter to the campus paper decrying security guards from removing students from the school’s grass, defending the right of students to sprawl and read on the leafy quad.

Sanders' push for making higher education available to all made him a darling on college campuses across the nation during the presidential election, and he joined Gov. Andrew Cuomo in January when the governor first announced his plan to make college tuition-free to SUNY and CUNY two- and four-year colleges for families earning under $125,000 a year.

At the commencement, once again he urged the country to follow other nations by making public colleges free to all.

Sanders has also been a defender of women’s, immigrant and LGBT rights and his support of progressive causes like living wage, parental leave and equal pay for equal work helped push the Democratic platform to the left during the presidential campaign.

Michael Wilkenson, who graduated with a Bachelors degree in political science and another one in film and television said he was pleased to see things already changing with regards to free tuition in New York.

“I’m looking forward to the momentum. There’s already been some progress,” said the 22-year-old from Sheepshead Bay. “I know that Trump is really bad, but with the words of encouragement that Bernie was talking about, I feel we can create a change. Our generation will change things.”

Sanders was far more popular during the primaries for the 2016 election than any other candidate. As of June 2016, with 21 states having cast ballots, he won more votes from the under-30 set than Hillary Clinton and Donald Trump combined, with more than 2 million young people casting ballots for him, according to the Washington Post.

City Councilman Juamaane Williams, a Brooklyn College graduate and proud Sanders delegate, said, "Sanders lost a race, but he won a country."

The senator is now a beloved celebrity that everyone wants to take pictures with, Williams said — and he helped turn a lot of people into progressives.

Public Advocate Letitia James commended Sanders as a “fellow progressive fighter,” asking the crowd if they could “feel the Bern.”

“People around the country talk about the resistance. In Brooklyn, we have long been the resistance,” James said, that the borough has long stood for: tolerance and acceptance of immigrants and refugees.

“Diversity and inclusion are our strengths, not our weakness,” she said, quoting the Notorious B.I.G, “'Here we spread love, it's the Brooklyn way.'"