Former President Donald Trump on Sunday made his first speech since leaving office in January, blasting his successor for having "the most disastrous first month of any president in modern history."

In his keynote address to the Conservative Political Action Conference, Trump attacked President Biden on many fronts — from immigration to national security to Biden's pandemic response.

"Already, the Biden administration is proving that they are anti-jobs, anti-family, anti-borders, anti-energy, anti-women, anti-science," Trump told the conference. "In just one short month, we have gone from America first to America last," he said, nodding to his self-described "America first" platform.

Trump hit on a familiar list of boasts and insults, and spent a sizeable portion of his remarks on immigration, accusing his successor of "eliminating our [southern] border" and triggering "a massive flood of illegal immigration."

He also blamed Biden for school closures that began during his own tenure, due to the pandemic, saying that Biden "caved to the teacher's unions."

Biden has said his goal is to have the majority of schools open for in-person learning within the first 100 days of his administration.

"They're cheating the next generation of Americans out of the future that they deserve and they do deserve this future," Trump said. "They're going to grow up and they're going to have a scar."

Trump criticized by name fellow Republicans who voted to impeach him after the Capitol insurrection, and he stressed that the party's rank and file is with him. He pledged not to start a third party, and added that he'd work to elect Republicans.

Trump repeated falsehoods about winning the 2020 election, and teased a potential 2024 run: "Who knows? I may even decide to beat them [Democrats] for the third time." Trump lost the Electoral College and the popular vote in 2020.

The former president easily topped the conference's annual straw poll. Fifty-five percent of CPAC attendees said they want Trump as the Republican nominee in 2024.

Second was Florida Gov. Ron DeSantis with 21% (CPAC was held in DeSantis' home state). With Trump not on the ballot, DeSantis was the top choice, followed by South Dakota Gov. Kristi Noem. Both made speeches this weekend and were received warmly.

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