Leaden Weapons and Lead Balloons
Historical analogies are such a poor guide to political action in the present that the most useful thing professional historians can do to promote sensible policies is to point out the limitations of history itself. That’s hard to do, however, because to deny that history repeats itself is to recognize the scary fact that what’s going on is literally unprecedented. Just as original writers have no way of understanding themselves except by misidentifying with some illustrious predecessor, historical actors and the rest of us in the terrified chorus imagine that we are repeating what is really happening for the first time. But every peace conference is not a Munich. Iraq is not Vietnam. Bush is not William McKinley. The Republicans certainly don’t merit comparison with the fascists—at any event not until the trains start running on time in these parts. Debunking such analogies by bloodless analysis is rhetorically ineffective, though philosophically interesting. The other available strategy is to multiply instances in order to make them all weaker, an approach that also has the heuristic benefit of suggesting alternate ways of understanding what’s going on.
Finally no science or other form of knowledge can be more intelligible than its object. Induction works brilliantly on the energy levels of atomic hydrogen because every electron really is exactly like every other. Natural history and totemism work to the extent that there really are natural kinds whose identities and borders are created and maintained by specific mechanisms. Where no objective order obtains, empiricism merely produces learned superstitions like astrology or the stimulus response learning theories of the first half of the 20th Century. The social sciences are full of such chimeras. Grown academics actually publish cross-cultural studies claiming to show whether or not capital punishment reduces the murder rate as if Sweden and Texas were lab rats of the same strain. Cross-temporal comparisons of events are even more problematic since there really are similarities between societies functioning at more or less the same level of technology while the haecceity named by World War II has very little more in common with the War of the Roses than with the War between the Roses. Even to the extent that one can identify comparable objects of study in history—states, classes, leaders, ideologies, conflicts—the number of instances is far too small a sample of possible cases to permit a test of more than the crudest generalizations.