Extrapolations

Some advise on writing alternate history. Interesting piece.

I've got two alt hist novels out now and a bunch more coming. One of the problems, or challenges I guess, is coming up with the point of divergence (POD).

I have in the works (percolating in my head, that is) a novel called Pershing's War: 1919 about the Great War continuing and the Allied effort falling primarily to the AEF. I'm intrigued by the idea of the AEF pushing into the Saar and Ruhr. The book would be about Pershing and some of his subordinates, also a young Patton, Marshall, MacArthur, etc...

So the POD is the breakdown of armistice negotiations.  OK, fine. But how do you get to THAT point? Aha!

I've liked the idea, also, of an 1871 POD where America joins the Franco Prussian War, probably with the Brits. I have no idea how to make that happen, and until I find a POD that's doable I won't write it.

Aside from the above mentioned 10 mistakes alt history writers makes, there should be a 10 mistakes 'future history' or just plain sci-fi writers. Extrapolating is my pet peeve. That is, take things as they are now and simply assume that progression of events will continue. I mentioned Soylent Green the other day, and that's certainly what they did in that movie.  In the source book, Make Room, Make Room, Harry Harrison is actually doing the opposite. He wrote it in the mid 60s and that was still an optimistic time.

Things are bad, let's assume they get worse. In the 1980's there were people who assumed that by now Japan would rule the world and we'd all be using the yen.

Let's take current controversies, Muslim immigration and birth rates and assume in 50 years Europe has become Eurabia. Why not? Of course, I remember the oil shocks and 'peak oil'. How'd that work out? Which is why when I read the incomparable Mark Steyn, I take heart. We can't extrapolate right? Right?