takes as its premise Kennedy’s near-escape from the Dallas assassination attempt. The player takes the role of Kennedy, trying at once both to assure his re-election—there’s a “poll meter” to track progress—and to solve the mystery of who took the shots at him. Unconvincing but weirdly moving figures of Robert Kennedy and others appear on-screen. Images show the view from the desk in the Oval Office, and a “tape recording” provides important clues.

Perhaps alternate history has become so attractive because history itself has come to resemble fiction. The twenty-fifth anniversaries of key sixties events and the fiftieth anniversaries of World War II each raised unsettling “what if” questions. What if we hadn’t used the bomb? What if Kennedy had lived? The widening posthumous popularity of Philip K. Dick’s work has sent readers back to his classic 1962 vision of an Axis victory, The Man in the High Castle, and there are countless other Hitler-wins and Kennedy-lives scenarios. Also, we have a growing sense of the tentativeness of real history. The relentless logic of the Cold War carried with it the implication of a face-off lasting indefinitely, and it suddenly crumbled with the Berlin Wall. For many of us, a united Germany still seems like a “what if” alternate reality, even ten years later.

Francis Fukuyama’s grandiose 1992 proclamation of the end of history has already come to seem old and tawdry, just as ideologies that proclaim the inevitability of revolution from below or revelation from above appear equally bankrupt today. History no longer looks inevitable or divinely driven; our destiny is no longer manifest. The dizzying pace of the changes that brought Lech Walesa from house arrest to power and Nelson Mandela from prison cell to presidential palace has suffused the world with a sense that anything’s possible after the iron grip of the Cold War. What, then, is so privileged about real history, about the version of things that actually happened to occur?

Virtually all nineteenth-century ideologies were rooted in views of history as unfolding according to some single pattern, be it Marxist or capitalist or otherwise. Marxism’s crash is evident; the decline of capitalism’s unquestionability is less clear but just as sure: Mixed economies, changing rules of business, and uneven development have already made mid-century visions of progress look as hoary as the great socialist workers’ revolution. If history was once a single track, laid by the Union Pacific with generous land grants from the U.S. Congress, now it follows myriad parallel tracks or, better, layers of possibilities mica-thin and shimmery, a temporal phyllo dough.

Part of what alternate history does is play with the fact that things can change so fast. It always embodies an implicit commentary on real history. Exactly what you change when you change history shows what you think

is important in that history. Also, the focus on individuals echoes the general shift of historians away from the cliometric history that became popular in the 1970s and early 1980s, looking at masses of data about societies, and toward the role of leaders and even ordinary people caught in the right or wrong place at the right or wrong time—not only the world’s Mandelas and Walesas but its Oswalds and Rays and Lewinskys too.

Alternate history has its own history, of course. An early landmark was the 1931 publication of a collection of speculations called If It Had Happened Otherwise: Lapses Into Imaginary History, edited by a playful English poet named Sir John Collings Squire. One contributor was Winston Churchill, who offered an essay about the South’s winning the Civil War; others included André Maurois on a Louis XVI with some spine and Harold Nicolson on Lord Byron crowned king of Greece. In October 1936 The American Mercury published Virginius Dabney’s fantasy of a successful Pickett’s charge, “If the South Had Won the War,” whose ultimate outcome was that Huey Long became president of the Confederate States. A few more alternate histories sprouted among science fiction writers in the 1950s, but it was not until the 1960s that the genre gained real momentum.

For this writer, alternate history struck home one day in the 1960s, when I came across MacKinlay Kantor’s book If the South Had Won the Civil War, originally an article commissioned by Look magazine on the eve of the war’s centennial and published in November 1960. It was witty and lively, with an unforgettable scene of Lincoln’s being hauled off by Jeb Stuart’s troops. That book emphasizes, as does much alternate history, the power of the individual to change events.

Kantor’s key move is to kill off Grant, depriving the North of its best commander. The story turns on minute twists too: A child holds a kitten that is chased by a dog that scares a horse that rears back and falls on Grant. However, Kantor also suggests a measure of inevitability, having the South, the North, and the Republic of Texas move toward reunification in the twentieth century. At one point he philosophizes that the “fruit of history contains many seeds of truth; yet unglimpsed orchards might have bloomed profusely in any season were all the seeds planted and cultured before they dried past hope of germination.” He also has fun with footnotes, citing imaginary reference works and drawing whole new characters, such as a son Jeb Stuart never had. Woodrow Wilson emerges as the Confederate president whose impulses toward international order will lead toward reunification.

The alternate novelist’s romantic strain finds expression in Stonewall Jackson’s not being shot by his own men in the evening of his greatest victory at Chancellorsville, so he is there at Gettysburg to execute Lee’s plans with his characteristic boldness. Kantor’s account, like most accounts of a Southern victory—one

of the most popular alternate history themes—mines that single tremendous moment in which it is forever the afternoon of July 3, 1863; Longstreet’s brigades are assembling in the woods a mile away from the Union line, and the issue is still not decided. It’s a sweet spot in the Southern imagination, tantalizing, almost titillating. Southerners are drawn to it not necessarily out of sympathy for the Lost Cause but out of the very romance of its lostness. It is a form of Southern Gothic.

The prolific Harry Turtledove, probably the best-known practitioner of alternate history working today, offers a very different ending to the war in The Guns of the South. The premise is laughable when stated baldly: South African white supremacists use a time machine to send AK-47 rifles back to General Lee’s army, ensuring a sympathetic apartheid-based state to help defend them against the likes of Nelson Mandela. It’s the kind of idea a colorful and argumentative professor might choose to highlight an abstract classroom argument: “You’re not a technological determinist? Well, what if, say, General Lee had AK-47s?” But it is carried out in such effective detail that the distinguished Civil War historian James M. McPherson has called it the most fascinating Civil War novel he has ever read. Take that, Stephen Crane, Bruce Catton, and Shelby Foote!

Like The Guns of the South, Ward Moore’s Bring the Jubileeis a time-machine novel and meditation on the historical power of individuals versus impersonal forces. It takes place in 1952, when a system of indentured servitude, the industrial equivalent of sharecropping, has replaced slavery. The economies of both North and South are hobbled; social tension is extreme. The story culminates in actual time travel with the opportunity to reverse the course of events; it adds up to a graphic depiction of Lincoln’s warning that a failure to end slavery would undermine not only the South, but the freedom of the workingman in the North as well.

The Civil War and World War II are the dominant situations for alternate history, but there are many quirky premises, as I learned when I spent some time with the Uchronia web page, which under the heading “Divergence” offers a chronological index of tales by their historical year of departure from reality. Uchronia provides a reminder that the stock-in-trade of alternate history is not the story but the premise: the what-if. Only the really big changes are intriguing enough. Who can stay awake at night wondering what would have happened if Hugh Gaitskell had lived to be elected prime minister of Great Britain in the 1960s? (There are of course such moments that do matter, such as the assassination attempt on FDR shortly before his first inauguration, in which Chicago’s mayor Anton Czermak was killed.) Uchronia seems to have been assembled by

kids you knew in junior high school—those kids on the audio-visual committee who always knew how to set up the film projectors and who exchanged expertise about Sgt. Rock comics and the uniforms of the Afrika Korps.

The most impassioned devotees tend to be the sorts of people who revel in extremely detailed military games, with each artillery battery and quartermaster unit minutely replicated and maneuvered. The gamesmanship of premise building suggests the fanaticism of rotisserie-league baseball players, who make up their own imaginary rosters of real, statistically accurate players and face them off on the basis of those statistics, say, the 1927 Yankees against the 1961 Yankees. They also pit the Yanks against the Rebs with every unit and its complement of weapons added up. Since the pieces are familiar, the detail can often deliver. (American Heritage, it must be noted, lent its name and support to a 1995 CD-ROM simulation, The Civil War, in which the war can be refought with varying outcomes. This author remembers a 1960s board game that did much the same thing; it was called 1862 and took the premise that in that year anything was still possible.)

If alternate history often resembles a game, its roots lie in science fiction. It is almost always a kind of time-machine tale, whether a character or the author himself goes back and changes things. The difference from regular science fiction is that in this version the essential machinery is shuttled offstage, having already done the work in creating the premise. Military history dominates, with a strong bias in favor of technological determinism: Everything changes when the South gets repeating rifles or Hitler the bomb. But that makes history a mere matter of military procurement, with the change of weapons usually extreme. In the film The Final Countdown, the contemporary aircraft carrier USS Nimitz finds itself in the Pacific on the eve of the bombing of Pearl Harbor.

Some of the tales turn on more eloquent technological conceits. In the 1991 novel The Difference Engine, by William Gibson and Bruce Sterling, who were among the first writers tagged with the label cyberpunk, the jokes are as much literary and historical as technological. In an England where the information age arrives a century early, via a steam-powered computer, John Keats is not a poet but a showman who creates protocinema using complex mechanical screens controlled by punch cards, a sort of pre-liquid-crystal display.

Harry Turtledove’s annoyingly named Worldwar series has a race of vicious lizards attack Earth from space during World War II, forcing the Allied and Axis powers to work out an alliance to fight the invaders. This premise recalls Ronald Reagan’s remark to Mikhail Gorbachev that we all would get along fine if a threat from another planet materialized. (Flying saucer fans latched on to that remark as a sign that Reagan knew more than he was saying about

Roswell.) Again the execution is vital. Turtledove’s imagination is luckily far richer and deeper than his prose. As the nations unite to cooperate against the extraterrestrials, only the survivors of the Warsaw ghetto treat with the aliens; they have already seen that much inhumanity on Earth.

Not just changes in historical and political thinking, but in economic models and biological ideas and even physics itself may have helped fuel the rise of alternate history. Physicists are lately looking at “parallel universe theory” and the idea of a “multiverse.” This is unfathomable speculation from the far reaches of quantum physics and relativity theory, but in the late 1950s, physicists, in an effort to unify contradictory observations, began seriously to propose alternate universes. Einstein had said that God doesn’t play dice with the world; now scientists were arguing in effect that He did. The key problem—the apparently indeterminate position of subatomic particles implied by quantum physics—was the essential roll of the dice. The answer given by a minority of scientists, and more since, was that from each “throw” two possible universes resulted. Thus the totality was a multiverse, a floating crapshoot of every conceivable possibility. The result, at least in theory, as the IBM research scientist Clifford Pickover explains it, is a “quantum foam,” with the possibility of travel between universes via “asymptotically flat regions in space time geometry” and “worm-holes.”

And then there’s the rise of complexity theory. Associated with the Santa Fe Institute, an independent scientific research center, and popularized by the film The Lost World, the sequel to Jurassic Park, complexity theory argues that small historical events can become magnifiers, dropped pebbles that create ripples, then eddies, and finally tidal waves. It merges evolutionary statistics and economic thinking, and its visual equivalent is fractals, those irregular geometric forms that multiply into seemingly unpredictable landscapes. The historical equivalent is history’s momentous small bumblings: the driver’s wrong turn that brought Archduke Franz Ferdinand’s car to a stop in front of the assassin’s pistol; the chance British interception of the Zimmermann telegram that convinced Americans of Germany’s hostility in World War I. What if Castro had had the stuff to pitch in the major leagues (Philip Roth played with that one)?

Piquant as such wonderings can be, they of course can provide only the spice of history, not the whole meal. Even after reading Turtledove or Kantor, it is hard to believe that however decisive a defeat the North suffered at Gettysburg the Union would not have raised new armies to replace the shattered ones, its armament factories, bootmakers, wagon fabricators, railroads, and gunboats ultimately surmounting almost any number of lost battles to win the war. Yet the questions linger, never fully answerable. The Chancellorsville victory, followed up a few months later by a Gettysburg where Jackson,

still alive, once again led a bold, battle-winning charge, this time sending deer and raccoons scrambling through the Pennsylvania forests ahead of his troops—this might have brought the British or French in on the side of the South. And then what?

Alternate history at its best relates the uncertainties of the lives of great men and nations to those of the lives of ordinary individuals. The characters in many of the books signal that they sense they inhabit an alternate world, through their own sense of alienation. The first page of Bring the Jubilee makes reference to the sense of ennui in the defeated North. Philip K. Dick’s The Man in the High Castle features an alternate history novel that presents what we know as the true story of World War II’s outcome. “Amazing the power of fiction, even cheap popular fiction, to evoke,” one of Dick’s characters observes while reading it. “No wonder it’s banned in Reich territory.” That book within the book turns out to be somehow more real than the bleak reality of life in the Axis-occupied former United States.

Hollywood likewise has shown itself surprisingly subtle in playing with time and its diverging tracks, from Peggy Sue Got Married and the brilliant Back to the Future series, with its clever details such as when Michael J. Fox’s character, transported back to the 1950s, is assumed to be named Calvin because of the label on his underwear, to Sliding Doors, in which two plot forks are intercut, and Groundhog Day, in which time makes a repeating loop of a single day.

Such stories only increase the natural tendency we all have to play with the alternative possibilities in our own lives. Thinking about alternatives keeps one’s life on track, the recovery folks tell us, and I want people in power who think about alternatives too. I want people who keep the other guys’ bills in their wallets, people who are alive to possibilities, have a vision of what else might happen, if they screw up or even if they do nothing. Those who change history the most are those most aware that it can change, that it is malleable—but only in the present. It may not be too much to say that those ignorant of alternate history are doomed never to alter history.