I don't dispute the importance of water shortages as a source of conflict, but there are others.

I don't think that shortage of water or energy had that much to do with the setting of modern Israel in the first place, and the sunsequent events; though of course those kinds of issues have helped make the consequences for Palestinians worse than they otherwise might have been.

Similarly, I don't think it was shortage of oil that caused a bunch of Saudi Arabians to get involved in the events of September 11. (And if you've got enough energy to spare, there's no shortage of desalinated water.)

And the troubles in Ireland haven't by any means been just or primarily a matter of poverty related to lack of energy supplies.

And Timothy McVeigh and such like don't really fit into that picture either.