Historian David J. Garrow acknowledges that he’s “cynical” about Barack Obama, a conclusion that he reached while conducting 1,000 interviews and spending nine years researching the formation and political rise of America’s 44th president.

Garrow shared some of his reasons for what he called his “huge disappointment” with the Obama presidency at a Zócalo/KCRW “Critical Thinking with Warren Olney” event, “How Did Barack Obama Create Himself?”.

Hosted by Olney, the longtime KCRW radio personality and dean of Los Angeles news broadcasters, the evening echoed many of the thematic lines—and withering criticisms—that surface in Garrow’s 1,400-page biography Rising Star: The Making of Barack Obama. “It’s worth reading,” Olney quipped, “but it takes a long time.” (Most reviewers agreed: The New York Times appraised Rising Star as “impressive if gratuitously snarly,” while Politico judged it to be “a masterwork of historical and journalistic research.”)

Published last spring, the book charts his subject’s transformation from a highly intelligent, rather aimless young man into a calculatingly ambitious politician who, according to Garrow, wore various masks at various life stages, walled off his emotions when it served his career goals, and remained an enigma even to friends and lovers.

“It has to be said that from at least 2001, 2002, Barack Obama has been first and foremost, fundamentally, a politician,” said Garrow, the author of well-regarded books on the Roe v. Wade Supreme Court case, the Civil Rights Movement, and the FBI. “There’s a very absolute compartmentalization that Barack imposes on his life, even as a 25-year-old.”

Garrow sketched out an abbreviated version of his book’s sometimes unflattering portrait of Obama, drawing applause and nodding assents, as well as occasional gasps and murmured objections, from the overflow audience.

Following Olney’s line of questioning, Garrow started out by discussing Obama’s high school and college career, his stint as a Chicago community organizer, and his youthful romantic life. Garrow faulted the future president for dumping Sheila Jager, the half-Dutch, half-Japanese woman with whom he lived for two years in the late 1980s, because Obama had made a determination that having a white wife would have been “a political non-starter” for a black politician in the Chicago of that time.

He said that Obama, born in Hawaii and raised with a “friendship network” of international students, only really began living among African Americans once he moved to Chicago and set his sights on a political career.

In Garrow’s view, Exhibit A in the saga of how Obama selectively re-invented himself is his 1995 best-selling memoir, Dreams From My Father, a reflection on his upbringing and his absentee Kenyan father. In Rising Star, Garrow describes Obama’s book as “a work of historical fiction.”

Garrow said that, in Dreams of My Father, Obama was “making a very conscious effort to reconstruct his life as dramatically more African American than it really was.” He also was attempting to re-cast himself as a rebellious tough guy, rather than the academically gifted nerd he really was, according to Garrow.

At one point, Olney quoted from the Rising Star epilogue that Obama had “willed himself into being” and that “the crucible of self-creation had produced an iron will,” but “the vessel was hollow at the core.”

“That’s pretty rough,” Olney said.

Garrow—who late in the evening described himself as “a Bernie Sanders Democrat” and “a great fan of Edward Snowden”—conceded that it was. But the author’s strongest criticisms centered on what Garrow regards as three key ways in which Obama walked back key campaign promises: by accepting large amounts of private campaign financing; by presiding over the growth of the federal government’s surveillance and anti-terrorist apparatus; and by retreating from support for same-sex marriage until Vice-President Joe Biden “got out there first.”

In response to Garrow’s comments, Olney asked whether Obama was really so different from other politicians who realized, once they got elected, that their campaign promises had to yield to more pragmatic considerations. Had Abraham Lincoln been “absolutely consistent in the things he said and the things that he did?” Olney asked, drawing one of the night’s biggest applause lines.

“I probably frankly have never read an Abraham Lincoln biography because I am almost entirely a post-1945 person,” Garrow replied.

Noting that Obama had read the first 10 chapters of Garrow’s book, Olney wanted to know what the former president thought of its less-than-glowing appraisal.

“The impression I came away with,” Garrow responded, “is that when someone has written up a version of their life story, at that point 20 years earlier, they remember better and remain attached to the version of their life which they wrote than the version which they lived.”

But if Garrow was unsparing in his remarks on Obama, he saved perhaps his harshest rebukes for Obama’s successor, Donald Trump, and the current U.S. Senate candidate from Alabama, Roy Moore—and for the American people themselves.

“The last 13 months again highlight, to me as a political historian, how American public opinion, oftentimes, lots of times, at a mass level gets huge numbers of things fundamentally wrong,” Garrow said. “I think there is a deep weakness in the American people, in American public opinion. I think there is a deep vulnerability to ignorance in American culture and American opinion that we continue to see, and that I fear we will see again next Tuesday, Dec. 12 in Alabama.”

Reed Johnson is managing editor at Zócalo Public Square.