In some ways people engaged in terrorist campaigns are very like governments (leaving aside the point that quite often governments are themselves engaged in what are by any reasonable standards "terrorist campaigns").   

Governments enter into a war with one set of war aims. But typically if that war lasts for any length of time, war aims change, sometimes drastically. Forget the stuff about WMDs, it's regime change that we set out to achieve; be realistic about that human rights stuff, it's stability that matters.

"Rationality" can mean two things - it can mean setting out to achieve ends which are "rational". Agreeing on what counts as rational is a minefield, but I doubt if I would see the overall goals of "Al Qaeda" as that kind of rational. (Though I wouldn't see the goals of a lot of the people in the other corner as too rational either.)

But it can also mean acting in a way that is designed to achieve the goals you have set yourself, however irrational those goals may be. And here I don't agree with writing off "Al Qaeda", because it seems to me they have rarely put a foot wrong in that way. And it doesn't seem to me that massacring innocent people implies any particular hate for them, just a ruthless decision that they are expendable, and that their death is useful in some way.

I don't think that the destruction of Hiroshima, 60 years ago this week, was the outcome of particular hate towards the people who lived there, or was irrational in that latter sense. I doubt very much if the train bombers actually felt much in the way of hate towards their fellow passengers. Insofar as the aim is to widen and deepen the rift between Muslims and the rest of society, by making Muslims a focus of hate and distrust, this bombing campaign could well acheve that, and therefore in that liited sense is perfectly rational.