Ten years ago, I made the following bet with French Israeli professor Raphael Franck:

If the total number of deaths in France from riots and terrorism is less
than 500 between May 28, 2008 and May 28, 2018, Franck owes me $50. If
the total number is 500 or more, I owe him $50.

Over this period, the total number of deaths in France from terrorism was 265.  (Wikipedia’s numbers come from the canonical Global Terrorism Database).  I cannot find any official statistics on rioting deaths.  But even the most famous riots during this period appear to have a cumulative body count of zero.  I have therefore won our bet – and by a large margin.

Prof. Franck, to be fair, disputes this determination.  With his permission, I’ll soon post his alternative count in his own words.  The key disputes, as far as I can tell:

1. Franck counts the Germanwings Flight 9525 incident as terrorism, even though almost no informed observer concurs.

2. Franck counts almost all people killed by French police during this period as “rioters.”

Needless to say, I maintain that my victory is beyond reasonable doubt – though I do regret my failure to pre-specify an official data source and arbiter to avoid this impasse.  I should have taken Tetlock even more seriously than I already do.

Still, my current track record now stands at 18 wins, 0 losses.  And out of all my bets I’ve won so far, I think we learn the most from this one. 

To see why, imagine that Franck and I had publicly disagreed about whether French terrorism and riots would be a “severe problem in the next decade.”  Looking back, virtually everyone would agree that Franck was right and I was wrong.  Every incident in France would be treated as further proof of my Pollyanna blindness to the horrors of the world. 

Since we settled on a specific number, however, fair-minded spectators will now see a very different story.  Franck – a vocal pessimist on these matters – wouldn’t have bet if he didn’t expect the standard number to be worse than 500 – probably markedly worse.  Hence, contrary to casual observers, the pessimists were not “vindicated by events.”  Far from it.

The flip side, of course, is that I would not have agreed to 500 if I didn’t expect a lower number.  What actually happened stands at roughly the 80th percentile of what I expected based on long-run base rates.  But statistically speaking, what occurred remains a tiny problem.  Over a thousand people are murdered on Earth on a typical day.  From 2008-2015 (the last available year), France’s murder rate ranged from 1.2 to 1.6 per 100,000.  That comes to roughly 800 murders per year in France, about 3% of them committed by terrorists. 

If ethnic Frenchmen from Breton or Normandy were responsible for a crime wave of this magnitude, would anyone outside of France even take notice?  It’s hard to imagine.  Would anyone in or out of France use it to justify any form of collective punishment?  Again, it’s hard to imagine.  But collective punishment is what terrorism-inspired immigration “reforms” around the world amount to.  There are many polite ways to say, “Most terrorist attacks are perpetrated by Muslims, so let’s keep Muslims out,” but good manners don’t change the fact that countries are punishing millions for the villainy of a small minority.

As someone who’s had a public conversation with Nassim Taleb, I know that terrorism has a big right tail.  But so do a great many risks that we calmly endure.  Every bite of food you take could be poisoned.  Every car ride you take could be your last.  Every baby born could be the next Hitler.  The sober response in all these cases is to exert moderate caution, not assume the worst.

Last question: Would I take the same bet again?  Yes, though only with a pre-specified data source and arbiter.  While things turned out worse than I expected, I also think that ISIS was a once-in-a-generation disaster.  Email me for specifics if you’re interested.