I ONCE carried into my lecture room The Law of Targeting by William H. Boothby. A student asked if the title was not a contradiction in terms. That’s the kind of question people ask whenever I give talks on the ‘laws of war’ — how can there be any law intact during war? Isn’t conflict defined as the complete breakdown of all laws and rules? In reality, though, there have been extensive efforts behind creating a body of law that regulates war — including the selection of targets. From the Lieber...