There's been a lot of interesting debate over gender and the recession and terrorism, but I think Plotz's take-away was misleading or even wrong. A lack of women in general isn't the problem - the ME has the same 1.05 male to female ratio as the world in general, whereas the comparatively successful India and China which have some of the worst ratios in the world at 1.12 and 1.1 respectively. While more women would ideally be in politics, they aren't completely absent (e.g. Benazir Bhutto, Queen Rania) and it's not really remarkable that a group of countries mostly lead by autocrats also happens to be mostly led by men.

The argument I've heard is that it's the lack of marriage prospects that causes young men to become alienated and prone to extremism, which is why traditionally polygamous ME countries are having these problems. There are some sub-Saharan African countries that are polygamous as well, and I don't know if they're having problems with terrorism, so that might be a hole in the hypothesis.