Did John F. Kennedy’s sexual frustration lead to the Bay of Pigs invasion, the low point of his presidency? That’s one of the loonier possibilities in British novelist Jed Mercurio’s American Adulterer, which puts us inside JFK’s obsessively womanizing thoughts during his White House years. This fictionalized but thoroughly researched account has the president believing that not having enough sex clouds his judgment. And he was so trying to be good during his early months in office that his sex-deprived mind wandered while he was being briefed on whether U.S.-backed forces should enter Cuba at the Bay of Pigs, as “delirium fogs his perception of the generals.”

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He did order that disastrous invasion, of course. Well, he wouldn’t let brain-fogging marital fidelity ruin foreign policy again. After a night with Marilyn Monroe, he finds that he is “lucid and decisive” once more, and feels free to screw around in the White House. He did it for the country!

American Adulterer is a more serious novel than the character’s silly justification makes it seem. Mercurio, who trained as a doctor, takes a medical approach to Kennedy, whom he refers to throughout the book as “the subject.” It’s a useless strategy, because no doctor’s voice separates JFK’s weird wishful thinking from what might be plausible. But with political sex scandals erupting all around us—John Edwards, John Ensign, Mark Sanford, it’s hard to keep track— American Adulterer holds its own fascination as it tackles the question we want answered most: What was he thinking? And what was she thinking, the suffering wife by his side?

The real Kennedy, the granddaddy of all hound-dog politicians, displayed the self-indulgence that leads to a classic chicken-egg question: What comes first, the outsized ego that makes someone think he can do anything (cheat, run the free world), or the power that deludes him into believing he can get away with it? The pre-presidential escapades of Kennedy and Bill Clinton suggest the former, but you never know. Mercurio’s Kennedy can’t shed much light on this because he’s already in power as the novel begins.

He’s also in constant physical pain. The clunky novel includes page-long excerpts from Kennedy’s speeches and alarming lists of his medical ailments. As recent historians have revealed, Kennedy’s illnesses were so debilitating it’s a wonder he could function at all: His back was a nightmare; he had Addison’s disease, an adrenal deficiency whose drug treatments created a host of side effects; he supplemented those prescriptions with amphetamine shots from a physician nicknamed “Dr. Feelgood.” As Mercurio puts it, Kennedy suffers from “Addison’s disease, thyroid deficiency, gastric reflux, gastritis, peptic ulcer, ulcerative colitis, prostatitis...” The list goes on for four more lines, and it’s only one of many such lists in the book.

Such clotted writing makes American Adulterer more interesting to talk about than to read. Mercurio himself (he turned an earlier novel into a sharp hospital drama) discusses the novel quite smartly in a video interview in which he flat-out says what the book leaves us to guess: that he regards his character’s belief that he needs sex to be a good president as medical nonsense.

Catchy though its title is, American Adulterer is not about a phenomenon unique to this country. When Britain’s Profumo scandal erupts, the fictional Kennedy worries that something similar could happen closer to home (worth worrying about, because J. Edgar Hoover is trying to blackmail him with FBI evidence of his flings). And Mercurio’s book only sounds like a companion piece to Curtis Sittenfeld’s engaging novel American Wife, which gets inside the mind of a Laura Bush-type character. The dark secret that Sittenfeld’s almost-Laura carries is not sexual but political: She knows George W. is a dreadful president.

What comes first, the outsized ego that makes someone think he can do anything (cheat, run the free world) or the power that deludes him into believing he can get away with it?

Instead, American Adulterer shares its crucial what-were-they-thinking theme with The Good Wife, CBS’s smart, absorbing fall series with Julianna Margulies as a betrayed political wife who undeniably echoes Silda Spitzer. The pilot begins with Margulies’ character, Alicia, standing ashen-faced next to her husband, Peter (Chris Noth), at a press conference as he resigns, admitting that he had sex with prostitutes. So far, the Eliot Spitzer story is depicted with Law & Order’s ripped-from-the-headlines fidelity.

Then we have some shrewd, timely twists. “You all right?” Peter asks Alicia after the press conference and she slaps his face. (A cathartic moment we can only hope played out in real life.) A non-Spitzer turn sends Peter to prison on a corruption charge, and Alicia back to work at a law firm (yes, Silda once practiced law, too). And at the end of the first episode, Alicia has a drink with a female colleague who speaks for all rational women when she says, “You know what I don’t get—why you stood by him. I would have stuck a knife in his heart.”

Alicia answers, “I always thought I would, too. When I heard about those other scandals, the other wives, I thought: How can you allow yourself to be used like that?” So far, so sane. “Then it happened and I was...” she says, struggling to explain even to herself, “unprepared.” And because this is cliff-hanging television, at that very moment her phone rings with the news that the jury in her case has a verdict. But we know Peter is appealing his conviction and wants her back, and I can’t wait to follow this tough thoughtful heroine as she chooses.

Trying to fathom the loyal wives’ response has kept us watching recent real-life soap operas like Elizabeth Edwards’ interview with Oprah Winfrey as she promoted her autobiographical book Resilience on what was quickly called her “revenge tour.” But Edwards didn’t really tell us why she stuck with her cheating spouse. (We can guess—the children, her illness—but that’s not the same as knowing.)

Mercurio’s Jackie Kennedy sometimes voices suspicions, sometimes quietly seethes, and usually does some heavy retaliatory shopping. The fictional Kennedy remains guilt-free about his affairs. How things have changed. Today we’re glued to Mark Sanford’s entertaining, confessional TMI press conferences. But there is more than voyeuristic curiosity involved. We may not be entitled to intrude on politicians’ private lives, but we deserve to know what kind of judgments officials are making, especially if they decide to go AWOL in Argentina. And, OK, there is some voyeurism, but of a kind that cuts deep into the culture. We’re still waiting to see if Jenny Sanford, now on vacation with her husband, will take him back or slap his face, will turn out to be a Stepford wife, a feminist heroine or something else entirely. Whether she likes it or not, her decision matters to American women.

Political sex scandals are a front-and-center part of the culture, becoming more bizarre every day. (The Clinton-Lewinsky scandal is so 1990s!) No wonder novels and television shows are questioning the adulterous lives and scheming brains of politicians and their spouses, even if the answers so far are half-baked.

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Caryn James is a cultural critic for The Daily Beast. She also contributes to Marie Claire and The New York Times Book Review. She was a film critic, chief television critic and critic-at-large for The New York Times, and an editor at the Times Book Review. She is the author of the novels Glorie and What Caroline Knew.