Would an Israeli strike on Iran be legal?

Brazilian foreign minister Antonio Patriota tells Laura Rozen that the UN Secretary General should speak out on whether a strike against Iran would be legal:

"No doubt adding an additional flashpoint of military action in a volatile region will greatly exacerbate tensions," Brazilian Foreign Minister Antonio Patriota told Yahoo News in an interview in New York Tuesday. The international community should proceed "with the utmost caution."

"There is a role for him in this," Patriota said he had proposed to the UN chief. "One sometimes hears the expression, ‘all options are on the table.’ But some actions are contrary to international law."

I actually wouldn’t be shocked if Ban Ki-moon took him up on the invitation. Ban’s a second-term chief, so he need not worry about angering key UN members (namely, the United States). And if he were to come out with a strong statement against the legality of a strike, he’d win praise for having tried to help avert a conflict (without actually having done so, of course).

On the substance of the legal question, Israel has a steep hill to climb. The basic UN Charter structure has been broadly interpreted to provide that a lawful use of force must either be in self defense or authorized by the UN Security Council. There’s almost no possibility of the latter, so Israel would have to hang its hat on self defense. And Israel could marshal an impressive body of statements from Iranian leaders suggesting that Iran is functionally in a state of war with the Jewish state. Consistent Iranian support for Hezbollah and other militants attacking Israel bolsters the case. The argument here wouldn’t be preemptive self defense (which would be a real stretch); it would be that the two countries are already effectively in a state of war, and that a strike against Iranian nuclear facilities would be another phase in that ongoing conflict.

Israel might be able to make a distinct argument that a strike would be legal. Pointing to the actual practice of states–and with particular emphasis on the post-9/11 period–Israel could argue that a strike does not violate the UN Charter’s key provision restricting the use of force, Article 2(4). That article reads as follows:

All members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations. 

Over the decades, a number of legal scholars–including, notably, Anthony D’Amato–have argued that this provision is not the blanket prohibition on the use of force that many claim it to be. So long as Israel’s strike would not aim to dismember Iran or strip away its political independence, the argument would go, it’s not expressly prohibited. Writing in the July 1983 issue of the American Journal of International Law, D’Amato made just that argument regarding Israel’s 1981 strike against Iraq’s nuclear reactor:

[I]t is open to serious question whether Israel’s strike was a use of force against either Iraq’s territorial integrity or its political independence. No portion of Iraq’s territory was taken away from Iraq by the bombardment…Nor was Iraq’s political independence compromised. Iraq’s power was undoubtedly lessened, but in what sense was its governmental authority vis-a-vis other sovereign governments diminished?

Israel could point to a host of cases in which states used limited force and were not condemned in any way by the international community. NATO’s 1999 air campaign against Serbia would be a key exhibit. What’s more, in the case of Iran, Israel could claim to be advancing a goal–the ending of Iran’s nuclear weapons program–that does have clear international backing, as evidenced by multiple Security Council resolutions.

Neither of these arguments is likely to persuade many people. While the self defense argument has a surface plausibility, a strike directly against Iranian territory would be a radical escalation of what has been a low-level proxy conflict. Very few people will view an Israeli strike as anything other than the opening of a new conflict. The Article 2(4) route, for its part, radically diminishes the conventional interpretation of that provision. Even diplomats and lawyers sympathetic to the argument–including some in the U.S. State Department, I’d wager–aren’t likely to say so publicly. The United States has been cagey about the formal justification for many of its own counterterror strikes and clearly prefers to leave many uses of force in the legal murk.

But the complexity of the arguments that would be on offer may well induce the UN Secretary General to stay silent and let the Security Council speak for the organization.