Old Post: Originally this was an update to an earlier post, but I decided to bump it and give it its own post. The original post is here.
In my previous post, I showed a rolling plot of the number of Americans killed in terrorist attacks. The problem was that highly successful attacks tended to cause sharp peaks which skewed the data, so I've done a plot of the number of Middle Eastern Terrorism attacks per year affecting Americans. This is also a five-year rolling average, and I think it shows a much clearer trend. Number of attacks doesn't consider the effectiveness of attacks, so it's more of a measure of intent than competence. It includes attacks that resulted in injury and deaths, as well as kidnappings where the prisoner was released. It also includes bombings on American property which didn't hurt anyone. Once again, it also includes attacks on Israeli targets which killed and injured Americans. I need to control for those at some point, but not right away.
This shows a peak in the Eighties, a decline around 1990, but a clear upward trend in the late nineties. In this chart, the whole of 9/11 counts as only one attack.