Futurology: The Perils of Prophesy
You can see, demonstrated in the two posts just below, my ability to be spectacularly wrong in forecasting the future. In fact I blew it in forecasting such a near future that it was probably already in the past by the time you read it. I could say of New Hampshire that the polls were nearly as wrong as I was, but that is only to say that the tarot cards were nearly as useless as the goat entrails.
A fair counterpoint is that predicting an election is like betting on any discrete contest, like the canonical horse race. It isn't random, because neither horses nor voters are dice, but it is a sort of breaking point, where all the trends and possibilities converge and something happens. The question is whether whatever happens merely encapsulates the trends, or reshuffles the board. Not every crisis is a Seldon Crisis.
In the philosophy of history - which is to say, in speculating about history - this is the form taken by good old free will versus determinism. Is history shaped by Great Men (for whatever shade of meaning you want to assign to "men"), or are they mere pawns of events? Perhaps there is an intermediate case, where the great impersonal forces are waves on which leaders surf, hanging ten if they they judge the moment and have the skill to exploit it, wiping out if they don't.
In creating future histories (or fantasy-world histories, a similar exercise in faking it), our bias is inevitably toward the great impersonal tide.* The drive to the stars can be accelerated a bit by a von Braun, retarded a bit by the politician of your choice, but starships get invented sometime around 2150 anyway.
The corner of Romance that deals with history most directly, however, takes an opposite stance. Alternate History as a subgenre is all about the Point of Departure: "What if Napoleon had a B-52 at the Battle of Waterloo?" Not every variant history is AH in this technical sense. There is a small - not even generally recognized - subgenre of parallel histories that resemble our own but never branched off from it, and much fantasy has pseudo-historical settings more or less synologous to some historical period.
As an established subgenre, Alternate History focuses not so much on the Point of Departure itself as its aftermath. The ur-classic of the genre is probably Lest Darkness Fall, a book that taught me essentially everything I know about the Ostrogoths, Belisarius, Justinian, and All That. An American archeologist is jolted back to AD 535, happily armed with the knowledge of how to puzzle out Late Vulgar Latin and distill rotgut brandy. Thanks in no small part to said noble potion, darkness does not fall.
Long before Lest Darkness Fall, of course, was A Connecticut Yankee in King Arthur's Court. But there the impersonal forces win out, and history is not changed after all. For Mark Twain, darkness does fall.
In the long run, in fact, most Alternate History ends up working out more or less this way. Apart from ever popular biases - a world divided among half a dozen empires, a surviving Confederacy, airships - the histories spun out on a site like AlternateHistory.com tend over the long run to run parallel to real history, especially as regards technology. History may be chaotic, but it is hard to think about, or make it up, in a chaotic way.
* If you are 'Murrican, be part of the great impersonal tide - vote in your state's primary or caucus!