(Posted by John.)
I'd like to pick up Ezra's "war is hell" message from a few days ago and run with it a bit, if I may...
In sustainability circles, there's a phrase known as Jevon's Paradox. Roughly stated, Jevon's says that as the efficiency of use of a particular resource goes up, consumption also goes up. Even Wikipedia notes that this isn't actually a paradox - as the efficiency goes up, the costs go down, so consumption increases. This is manifested today by more efficient air conditioners leading to greater use, for example.
I've been wondering lately, however, if there isn't a military application to Jevon's.
