Modern U.S. presidents such as Barack Obama and Ronald Reagan rank near the top of the best leaders in American history, while Donald Trump is closer to the bottom, according to the latest survey of presidential historians.

The five highest rated presidents, according to the C-SPAN survey, are Abraham Lincoln, George Washington, Franklin D. Roosevelt, Theodore Roosevelt and Dwight D. Eisenhower. The bottom five include William Henry Harrison, Donald Trump, Franklin Pierce, Andrew Johnson and James Buchanan.

What the presidents at the very top of the list have in common is that most faced monumental challenges related to the nation’s survival. Lincoln presided over the Civil War and kept the country from breaking apart. Washington, America’s first president, helped nurture the budding democracy by not becoming king and stepping down after serving as president. Franklin Roosevelt presided over America during World War II and Eisenhower negotiated an end to the Korean War.

“They were all president during critical periods in American history,” says Cassandra Newby-Alexander, dean of the College of Liberal Arts and a professor of history at Norfolk State University, who took part in the survey. “And all of them, from John F. Kennedy (8th), all the way up to Abraham Lincoln (1st) created some idealized vision of America.”

Source: C-SPAN

Source: C-SPAN

The presidents were judged on the vision they had for America, public persuasion, crisis leadership, economics, moral authority, foreign affairs, administrative skills, relationship with Congress, pursuit of equal justice and their performance within the context of the time they led the country.

Political scientist Robert Kaufman, a professor of public policy at Pepperdine University, who also took part in the survey, says it is important to make a distinction between greatness and an effective president.

“Not all very effective presidents can be great, in my estimation, because greatness also depends upon the magnitude of the challenge,” he says. “Theodore Roosevelt, at the beginning of the 20th century, and Bill Clinton, at the end, were effective, but never faced the type of challenge that would lend itself to greatness.”

The man at the bottom of the list, James Buchanan, is often ranked as one of the worst U.S. presidents. His refusal to take a side on slavery, while at times siding with slaveholders, is thought to have inflamed divisions within the country ahead of the Civil War.

James Buchanan, 15th President of the United States (1857-1861)

James Buchanan, 15th President of the United States (1857-1861)

Both Kaufman, who calls himself a Republican, and Newby-Alexander feel Truman (6th) might be the most under-rated president. Both point to his fight for civil rights while Kaufman also praises the 33rd president for “laying the successful architecture for winning the Cold War.”

Overall, Newby-Alexander says, the survey results reflect a conventional view.

“If you consider the average age of historians, they tend to be older, they tend to be white and they tend to be male, so that actually leads to many of them having a somewhat traditionalist perspective,” she says, pointing out how high Theodore Roosevelt (4th) and Woodrow Wilson (13th) ranked despite their well-established racist views and actions.

“Under their administrations, we had the largest number of concentrated lynchings that went unpunished than any other time in American history,” she says. “[Wilson’s] the one who strictly segregated the federal government. That did not exist before. He segregated the Navy. That did not exist before. He initiated a lot of very retrograde policy during a critical period in American history.”

FILE - President-elect Woodrow Wilson and President William Howard Taft laugh on the White House steps before departing together for Wilson's inauguration in Washington, D.C., U.S. in March 1913.

FILE – President-elect Woodrow Wilson and President William Howard Taft laugh on the White House steps before departing together for Wilson’s inauguration in Washington, D.C., U.S. in March 1913.

The passage of time and the gaining of perspective tends to change how presidents are viewed. While Newby-Alexander thinks Reagan (9th) is overrated, specifically mentioning his stance on apartheid — he vetoed the Comprehensive Apartheid Act, which levied economic sanctions against South Africa in 1986 — Kaufman lists the reasons he would push the 40th U.S. president higher up the list.

“Winning the Cold War, restoring American economic prosperity rooted in Judeo-Christian values, and optimism about America’s exceptionalism,” Kaufman says. “He understood a) what the Soviet threat was about, b) what we needed to do to defeat it, and he left Bill Clinton a very strong hand. In many ways, we’ve been living off borrowed military capital of the Reagan buildup of the 1980s, when he inherited a military in disarray.”

And, although he says it might be an unpopular opinion, Kaufman thinks Trump (now ranked 41 out of 44 presidents) will also rise in future surveys.

“I think that, as the years go by, the president will get credit, however sausage-like the process was, for putting certain issues on the table that had long been neglected — sovereignty, particularly China, and energy independence,” he says. “I think China, which is the dominant foreign policy threat of our time, by my estimate, is something where Trump will get more credit, substantively, not temperamentally, than one would rate him now in the wreckage of his presidency.”

Newby-Alexander believes history will judge Obama (10th) more favorably.

“I would have put Barack Obama under Abraham Lincoln because he managed to not only provide us with an incredibly important health care initiative — while it has a lot of flaws, it was something that presidents have been trying to do for almost 100 years, and he succeeded,” she says. “Also, he was someone who got us out of a crisis that was actually deeper than the Great Depression when the stock market crashed in 1929. What we experienced right before he took office was worse than what Franklin Roosevelt dealt with, and he was able to pull us out. And I think that that has been tremendously underrated.”

The current president, Joe Biden, is not on the list, and historians say it is too early to judge him.