YOU CAN CHECK OUT ANY TIME YOU LIKE, BUT YOU CAN NEVER LEAVE: Despite describing himself as a "lapsed historian," Joshua Marshall returns to his roots in a brief review of the book Moorish Spain by Richard Fletcher. Marshall notes that:

This isn't the sort of thought one is supposed to allow oneself in a book review - even a casual one. But what I find so captivating about this topic is how striking it is that this part of Europe - deeply Christian, speaking a Romance language, part of the western fringe of the Roman Empire - was Muslim for more than half a millenium. Mosques ruled over churches. The Christian population slowly converted to Islam. Arabic became the lingua franca - at least for the more refined and cultured portion of the population, and at least in the great cities. It's all very alien and weird - an alternative possibility for how Europe might have developed - and thus fascinating.

I don't see what's wrong with that thought - why isn't it appropriate to see the "alternative possibilities?"
UPDATE: Mr. Marshall has clarified that the thought one isn't "supposed to allow oneself in a book review" was the personal reaction of finding something "captivating," not the substance of the thought itself. Either way, I don't see a problem (and apparently he doesn't either.)