O. J. Simpson, Monica Lewinsky, Timothy McVeigh—seeds of the present? Illustration by Concepción Studios; Clockwise from top: Michael Nelson / AFP / Getty (Simpson); Reuters / CORBIS (McVeigh); Barbara Laing / The LIFE Images Collection / Getty (Building); APTV / AP (Lewinsky)

History is the prediction of the present. Historians explain why things turned out the way they did. Since we already know the outcome, this might seem a simple matter of looking back and connecting the dots. But there is a problem: too many dots. Even the dots have dots. Predicting the present is nearly as hard as predicting the future.

Once, history was a game played with giant billiard balls: wars, revolutions, scientific inventions, the major awards shows. You knocked a combination of these together and you got our world. Then people realized that wars, revolutions, the Grammys, etc., are not explanations at all. They are themselves things that need to be explained. Something made them possible, too. Was it money? Ideas? Genes? Germs? Great men? Deepwater ports?

Histories are categorized according to what the historian has chosen as the basic unit of explanation. There are top-down histories, bottom-up histories, and sideways histories, histories in which causes have an oblique relation to effects. (Rome fell because the wine jars were made of lead—a fun explanation, though somehow unsatisfying.) There is history of the longue durée, which doesn’t help us understand why 2015 is different from 2000 (or, for that matter, from 1900 or 1800). There is species history, which explains even less. Humans invented agriculture: bad news, end of story. And there is “history of the present,” which tries to see today the way historians a hundred years from now will see it—as one more slice of time during which people had no idea how completely wrong they were about everything.

No historian lines up all the dots. Every work of history is a ridiculously selective selection from the universe of possible dots. What the historian is claiming is that these are the particular dots that lead us from there to here, or from time step 1 to time step 1.1. Lots of other stuff happened, the historian will agree. But, if these things hadn’t happened, then life as we know it wouldn’t be, well, as we know it.

This can be an existentially entertaining thought—that, but for some fluky past event, experience would be entirely, or at least interestingly, different. We tend to imagine our own lives that way, a story of lucky breaks, bullets dodged, roads diverged on a snowy evening, and the like. Speculating about sparks that failed to ignite versus sparks that did and contingencies that failed to materialize versus contingencies that did is one of the reasons people like to write history and like to read it. There is even, to appeal to this taste, the subgenre of counterfactual history, in which Napoleon conquers Russia, or the Beatles give “The Ed Sullivan Show” a pass.

There are many ways of agglomerating past events, parcelling up old clicks of the clock and endowing them with collective meaning. There is the concept of the historical period: the Age of Reason, the long eighteenth century (which seems like cheating; if you call something a century, you should stick to a hundred years), the Victorian era, the Cold War, the all-purpose and infinitely capacious “modernity.”

There is the concept of the generation, an empirically specious category (as though the human race reproduced itself just once every twenty-five years) that nevertheless captures an element in everyone’s sense of identity. And, of course, there is the decade. For some obviously bogus reason, presumably because we have ten fingers, we find it natural to imagine that life assumes a completely new character every ten years.

Centuries, generations, and decades are terms of convenience. They attach handles to the past, they give titles to books, and, most important, they put a spin on a chunk of time and differentiate it from all the rest. They give history some coherence. But the most enjoyable histories to read (and, probably, to write) are “the x that changed the world” books. These are essentially one-dot explanations. They try to make the course of human events turn on a single phenomenon or a single year. Recent works in the single-phenomenon category include books on bananas, fracking, cod (that’s correct, the fish), the Treaty of Versailles, pepper, the color mauve, and (hmm) the color indigo. (All right, who’s the baddest color?) In the single-year category, we have books on 33, 1492 (huh?), 1816 (long story involving a volcano), 1944, 1945, 1959 (even though, without going to Wikipedia, you probably can’t come up with two important things that happened in 1959), 1968, 1969, and 1989.

Now there is W. Joseph Campbell’s “1995: The Year the Future Began” (California), a worthy, informative, and sporting attempt to convince us that the world we live in was crucially shaped by things that happened in 1995. (Campbell insists that there is a distinction between “the x that changed the world” books and his own “the year the future began” book, although it’s hard to grasp.)

The book is not completely persuasive, but that’s not important. None of the “x that changed the world” books are completely persuasive, for the reason that all dots have dots of their own. Unless you count God, there is no uncaused cause. Even the butterfly that started the hurricane flapped its wings for a reason. Whatever happened in 33 or 1959 or 1995 never would have happened unless certain things had happened in 32, 1958, and 1994. And so on, back into the protozoic slime. All points are turning points.

All points might not be tipping points. But that’s not what these books are arguing. They are seeking to confer before-and-after explanatory power on a single thing, or on what happened on a single date on the calendar. We can doubt the premise. But what the melodramatic titles are really and usefully doing is drawing our attention to something—pepper or 1959—that we might otherwise have ignored. Do melodramatic titles also sell books? So what if they do? We’re in favor of selling books.

Campbell’s book draws our attention to the nineteen-nineties. And he’s right when he points out that the decade is pretty much ignored. Maybe this is because many Americans remember the nineteen-nineties as a tranquil time or maybe it’s because the decade is wedged between two periods that attract a lot of industrial-strength historical notice: the Reagan era and the “age of terror.”

How tranquil were the nineteen-nineties? “Our Long National Nightmare of Peace and Prosperity Is Finally Over” was the headline in the Onion the month George W. Bush took office, January, 2001. His Administration took care of that in a hurry. In fact, though, the nineteen-nineties were not so peaceful. Dozens of wars were under way around the world. It’s just that, especially while Bill Clinton was President, the United States was involved in very few of them.

It was, however, genuinely a time of prosperity. In 1993, the year Clinton became President, median household income in the United States was $48,884. Six years later, it was $56,080, and the federal government ran a $125.6-billion surplus. There was an even bigger surplus in 2000, and ever since 2001 the federal government has been in the red. In 2013, median household income was $51,939, and the budget deficit was $680 billion (which was small by post-Clinton standards).