When Ronald Reagan biographer Craig Shirley was asked this week about a new survey of “scholars” putting President Joe Biden ahead of the Gipper as the 14th “greatest president” in history, he exploded.

“It made me gag,” Shirley said, hitting the “Presidential Greatness Project’s” experts as left-leaning educators.

“Joe Biden is a terrible, terrible person. He is going to go down in history by honest historians as the worst president in American history,” he added.

Shirley, who just debuted his latest work, The Search for Reagan, and is beginning on a biography of former President Donald Trump, didn’t stop there. “The idea that Joe Biden is a great president is just nonsense. It’s poppycock. It’s ridiculous. Name one thing that he’s been successful at other than spending money, and, by the way, any moron can spend money,” he added.

The survey was of members of the American Political Science Association who specialize in national and presidential politics. Presidents were ranked on a 0-100 scale.

The top five were not surprising for the liberal scholars. In order, they were Abraham Lincoln, Franklin Delano Roosevelt, George Washington, Theodore Roosevelt, and Thomas Jefferson.

The next five were more controversial: Harry Truman at No. 6, followed by Barack Obama, Dwight Eisenhower, Lyndon Johnson, and John F. Kennedy.

Reagan was 16th and Trump dead last at No. 45.

Looking at the Trump and Reagan placement also sparked a reaction from Shirley, who said that while the two former presidents were very different, they also had remarkable similarities on issues that matter.

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“Personally, their worlds apart. They’re different. They’re different men, but that’s just how they approach politics and life and culture and society,” Shirley said, highlighting the difference in the country between today and the early 1980s.

Still, he added, “The parallels are clear, more clear than I think people realize. One is that they both challenge authority. They both challenge the Washington establishment.”