Would Rocky Marciano have beaten Muhammad Ali if their primes had overlapped? Could Ted Williams have hit Bob Gibson’s fastball? Would John Kennedy have defeated Barry Goldwater in a race for president?

Jeff Greenfield is silent on boxing and baseball, but his current contribution to fantasy politics includes a Kennedy victory over Goldwater in 1964, following Kennedy’s survival of the assassination attempt by Lee Harvey Oswald 50 years ago this November. Fantasists will find “If Kennedy Lived” intriguing — students of the real world less so.

There are two reasons to engage in counterfactual history. Greenfield prefers the more lenient label “alternate history.” One is to identify critical events, hinge points of history, and analyze why they turned out the way they did. To ask whether there would have been a Cold War if Franklin Roosevelt had lived to complete his fourth term is to conduct a thought experiment on the causes of the breakdown of the Grand Alliance of World War II. Were personal considerations crucial — was Harry Truman overly suspicious, perhaps? Or were larger factors decisive?

The key to the usefulness of such experiments is controlling for everything but one variable. This is impossible, of course, but approximations can nevertheless be revealing. The trouble is that the approximations attenuate as the experiment progresses, for fiddling with reality creates its own context. In Greenfield’s case, he can imagine, with some confidence, what Nov. 23, 1963, would have looked like whether Kennedy had lived or died the day before. But as to November 1964, or July 1965, or any other date after that, he is just guessing.

Yet guessing can be fun, which is the second reason to engage in counterfactualism. Historical fiction has a long lineage. Homer, Shakespeare and Dickens indulged, as did countless authors less distinguished. Greenfield amuses himself concocting a second inaugural gala at which the Beach Boys sing “Fun, Fun, Fun (in a Second Term With JFK)” and Roy Orbison croons “Oh, Pretty Woman” (“This one’s for you, Jackie,” he says). Kennedy brings the Beatles to the executive mansion and declares, “Not since the British burned the White House in 1812 has a foreign invader conquered our land as swiftly and thoroughly as have John, Paul, George, and Ringo.”

“If Kennedy Lived: The First and Second Terms of President John F. Kennedy: An Alternate History” by Jeff Greenfield. (The Penguin Group)

More seriously (to the extent fantasy can be serious), Greenfield’s Kennedy successfully resists broad pressure to escalate the war in Vietnam. This has been the touchstone of the Camelot claque since the 1960s: that Kennedy would have had the wisdom and strength to keep America out of the morass that Vietnam became. The argument is not implausible. The real Kennedy did hint at a basic review of U.S. policy in Southeast Asia. And if he had won a second term, his lame-duck status would have granted him a certain political freedom denied to presidents who have another race to run.

But it’s worth remembering that the American effort in Vietnam looked promising to most observers until very late in what would have been that second term. Of course, Greenfield’s Kennedy is blessed with the author’s hindsight. Real presidents aren’t so fortunate.

In Greenfield’s telling, Kennedy pays for withdrawal from Vietnam with a decision not to press Southern conservatives on civil rights. He does win passage of a voting rights act with the assistance of Lyndon Johnson, who was forced off the second-term ticket after revelations of corruption in Johnson’s rise to power. Here Greenfield quietly acknowledges LBJ’s crucial role in the most important development of the Kennedy-Johnson decade: the revolution in civil rights. Absent Johnson — a Southerner who could speak to Southerners in their own language, and a legislator in chief par excellence — the Jim Crow system would have lasted longer, perhaps much longer.

Greenfield doesn’t ignore Kennedy’s indefensible personal behavior and failing health. His extramarital affairs imperiled his presidency and conceivably national security; Greenfield’s Kennedy survives his second term with his reputation intact, but barely. His health is another matter. By the end, the degeneration of his spine makes it almost impossible for him to walk. Like Franklin Roosevelt a generation earlier, he resorts to subterfuge to hide his disability from the American people. As for Kennedy’s marriage — on this subject the reviewer must be silent, lest the drama be spoiled.

Greenfield’s approach includes quoting historical figures, using their actual words but lifting them from context and setting them down to suit his fabricated tale. Knowledgeable readers will appreciate the artfulness of the method; others won’t notice the difference, sometimes to their detriment.

In this solemn season of Kennedy remembrances, and after decades of dark conjectures of conspiracies surrounding the assassination, Greenfield’s alternate history takes readers on a lighthearted romp through a fraught decade. But as they enjoy the ride, they should bear in mind the words of Thomas Brackett Reed, the legendary Gilded Age speaker of the House of Representatives, who said of a political opponent that he could not open his mouth without subtracting from the sum of human knowledge.

Greenfield courts a comparable feat here. His work engages and entertains, but by the very plausibility of its fictions, it risks leaving readers knowing less than they did before they picked it up.

H.W. Brands, a professor of history at the University of Texas and author of 25 books, has written about several presidents, including John F. Kennedy.


The First and Second Terms
of President John F. Kennedy:
An Alternate History

By Jeff Greenfield

Putnam. 249 pp. $26.95