Anthony Clark Arend at Georgetown University is blogging about Israel’s threat to bomb Iranian nuclear reactors if they do not desist. He worries that this latest brinkmanship is more evidence of a decline in the non-aggression norm, since the situation would not meet the criteria for preemptive self-defense against an imminent attack laid out in the UN Charter as an exception to the non-aggression rule:

If imminence is not the standard for using force anticipatorily, then what is? The mere fact that the other state is building a nuclear reactor? The fact that the other state is building a reactor and is hostile toward a particular state? The fact that the other state has a history of aggression? The problem is obvious. As fuzzy as the imminence criterion may be, if that criterion is relaxed, it is unclear what will replace it. And so, the door will be opened for more and more bogus claims of “legitimate self-defense.”

In other words, we’ll be back to plain old balance of power politics, a bad recipe in a nuclear armed world.

Arend’s discussion of the law on preemptive self-defense, and how it differs from the Bush doctrine, is extremely illuminating. I think he may be overestimating the damage being done to the norm itself here, however (much like those arguments I’ve heard that Guantanamo Bay “threatens the entire Geneva regime.”) I would say that in terms of norm decline, what matters is not what states like Israel or the US do, but how the international community reacts, since as Fredrich Kratockwil and John Ruggie long ago argued, “norms are counterfactually valid.”