“While nobody could have prepared for the grim reality of a Trump presidency,” writes Senator Al Franken in his new memoir Al Franken, Giant of the Senate, “when I look back at my own political journey, I can’t help but feel like I’m as prepared as anyone could be for this moment.”

The senator’s point is hard to argue. Mr. Franken’s circuitous path to the “world’s greatest deliberative body” started in the mid-1970s at Saturday Night Live, where he spent 15 years as a writer and performer before going on to become a best-selling author of political satire and a radio talk show host targeting right-wing media and politics. Who better to combat the absurd, dark joke at the heart of the rise of Trumpism than someone like Al Franken? The junior senator from Minnesota combines a keen intelligence and the rigorous instincts of a policy wonk with a deep understanding of media that enables him to detect the difference between manipulating an audience in the service of laughter versus a far more cynical agenda.

Who better to combat the absurd, dark joke at the heart of the rise of Trumpism than someone like Al Franken?

Giant of the Senate is a funny title in the Franken tradition, but a more accurate name might have been “The Making of a Senator.” Mr. Franken’s unique background presented challenges to getting elected to his first term in 2008, and a good deal of the book recounts how he balanced his need to be taken seriously with his natural comedic impulses. Dialing back the humor “wasn’t that hard; I wanted to win, you know?” he explained to me with a chuckle in a recent interview. During his first term, he decided to be a “workhorse instead of a show horse” and tried to keep a lid on the funny. (“The Angel and the Devil” chapter offers some amusing insight into his struggle.) Winning his second term in 2014 by a comfortable margin helped free him. “I think it was clear that the people of Minnesota kind of got what I was doing,” he said. “I was taking this very seriously so…I kind of felt like after that I could loosen up a little bit.”

The irony isn’t lost on him that, as he was trying to keep his humor in check, a large chunk of Americans were being roped in by one of the most disturbing jokes in U.S. political history. He mentions being at an event with Hillary Clinton and Huma Abedin early in the primary season and sharing that they all found Trump’s candidacy both fascinating and amusing. “I think that might’ve been the experience for a lot of people,” he told me. “Then I think the more and more you saw, I think the more serious and frightening it started to become.”

As Al Franken was trying to keep his humor in check, a large chunk of Americans were being roped in by one of the most disturbing jokes in U.S. political history.

Not only was Mr. Trump winning, but with the entrance of chief strategist Steve Bannon, who as the head of Breitbart News gave a “platform to the alt-right,” things got even uglier. “I think there were aspects of [Trump’s] personality which you might’ve thought, O.K., well he’s honed this personality as some kind of performance art, but then at a certain point you go, ‘Wait a minute, O.K., that’s not political performance art; that’s who he is.’”

For all the vitriol Al Franken’s name evokes among conservatives—due in large part to his provocative 2003 New York Times best seller Lies: And the Lying Liars Who Tell Them: A Fair and Balanced Look at the Right—it is important to note that Senator Franken’s satiric analysis was prescient. It is not difficult to connect the dots between his long-running examination of the right-wing media echo chamber that has been growing since the early ’90s and the political ascendance of Donald Trump.

But while Giant of the Senate resurrects Mr. Franken’s humor, it is also a window into something deeper.

But while Giant of the Senate resurrects Mr. Franken’s humor, it is also a window into something deeper. Whether it is his wife’s struggle with addiction in the late ’80s, the plight of military veterans today or even his many friendships with Republican senators (with the hilarious exception of Ted Cruz), Senator Franken’s depth of feeling is very much in evidence. “I never thought the funny was in conflict with anything in terms of being human,” he said through laughter. “It depends on how you use it. I am a pretty emotional guy and never found that humor was sort of covering up that.”

The lessons he learned from his deceased friend and political hero, Paul Wellstone—whose Senate seat Mr. Franken now occupies—serve as his compass. “Politics is not about power,” Wellstone said. “Politics is not about money. Politics is not about winning for the sake of winning. Politics is about the improvement of people’s lives.”

That sentiment was on display during Senator Franken’s recent grilling of Trump nominees for cabinet: Attorney General Jeff Sessions’s recusal from the Russia probe is grounded in challenging questions Mr. Franken asked him. It earned the senator enough good will that some have begun floating the idea of Al Franken for president in 2020—to which he told me diplomatically, “I have no plans.”

Given the current landscape, it is difficult not to ponder the possibilities. In a classic S.N.L. bit from 1979, Mr. Franken declared that the ’80s would be “The Al Franken Decade.” One wonders if Senator Franken may have been right all along, even if he was off by 40 years.

This article appears in August 21 2017.