AN OUNCE OF PREVENTION. Noam Scheiber responded late last week to my contention that Hezbollah posed no "mortal danger" to Israel by, in essence, agreeing with me. According to Scheiber (and I tend to agree), the Israeli government wasn't reacting to a perceived current or imminent danger but, rather, saw Hezbollah's cross-border raid as offering a reasonable casus belli for launching a preventive war aimed at curbing a perceived future threat from what was seen as Hezbollah's growing power. The difference is that I don't think this is a good idea at all.
Preventive war has always been regarded as morally suspect (see, e.g., this recent article from Michael Walzer) since it lacks the element of necessity that can justify the killing of innocents. In addition, were preventive war to be legitimized as a widespread tool of international conduct, the result might well be a general global downward spiral into chaos. Countervailing that risk is the simple fact that preventive war's historical track record is exceedingly poor. The major modern historical examples are that Napoleon in 1811 and the German government in 1914 both tried to wage preventive wars against Russia and wound up destroying their own regimes instead. The American invasion of Iraq in 2003 is, likewise, best understood as a preventive war and, likewise, hasn't gone well at all.
I tend to think we're seeing much the same thing in Lebanon. Just as we saw before the Iraq War, a lot of people are making the jump from "the status quo is bad" to "war is a good idea" without adequately considering how unlikely it is that war will improve the situation.