In all the talk and debate about possible U.S. or Israeli military strikes against Iranian nuclear development sites, there has been remarkably little discussion of international law. In a recent Washington Post Op-Ed, a former State Department legal adviser and former CIA general counsel lamented that there "has been almost no discussion of whether an attack by the United States would be legal." One might easily wonder, based on this near-silence amid public debates about red lines and likely effects of strikes on Iranian capabilities and regional politics, whether international law will really matter at all if the crisis should come to military blows.
But it will matter, because strategy and international law are entwined, a reality illustrated 50 years ago this week, in another nuclear showdown: the Cuban Missile Crisis.
On October 22, 1962, President Kennedy addressed the nation. In explaining that the Soviet Union had secretly and in violation of pledges begun moving nuclear missiles to communist Cuba, Kennedy explained:
"Neither the United States of America nor the world community of nations can tolerate deliberate deception and offensive threats on the part of any nation, large or small. We no longer live in a world where only the actual firing of weapons represents a sufficient challenge to a nation's security to constitute maximum peril. Nuclear weapons are so destructive and ballistic missiles are so swift, that any substantially increased possibility of their use or any sudden change in their deployment may well be regarded as a definite threat to peace."
This language and logic, similar to that used by American and Israeli government officials in explaining the dangers of a nuclear armed or capable Iran, was used at that time to justify the U.S. naval "quarantine" – really a military blockade – of Cuba to prevent further arms shipments and to signal U.S. willingness to escalate. Several days later, and under the specter of superpower conflict, the U.S. and Soviet leadership reached an agreement and the missiles were removed.
From an international law perspective, the U.S. government faced a problem, though. The quarantine was a "use of force," which is prohibited under the U.N. Charter except in cases of self-defense against an actual or imminent armed attack, or unless the U.N. Security Council authorized force (but that was impossible because the Soviets held a veto). Yes, nuclear missiles in Cuba were very destabilizing and threatening, but there was no indication that a Soviet attack was immediately impending. The U.S. government therefore decided to base its public justification on a resolution favoring the quarantine by the Organization of American States (OAS), even though this was at best a very weak legal argument (since the OAS could not authorize a use of force that was prohibited by the U.N. Charter). Because the stakes were so high and the U.S. legal arguments so thin in this eyeball-to-eyeball nuclear showdown, one might easily dismiss international law as having been irrelevant. International law shaped policy-making in some subtle but important ways, however, with lessons for the current face-off with Iran.
Today, it again seems implausible for the foreseeable future that the U.N. Security Council will authorize military action (this time because Russia and China would likely veto), so international law would demand that American or Israeli military strikes be justified under a theory of self-defense. Such an argument will depend on the facts at the time, but will no doubt face very skeptical audiences at home and abroad.
In the end, perceived strategic necessities eventually may again compel military action even without clear-cut legal authority – it is naďve to think otherwise – but law is itself a factor in that strategic calculus. Dubious legality makes military action more costly – including in terms of military, political, and diplomatic repercussions, as well as long-term precedent that may be exploited by others – and therefore affects its perceived merits relative to other options. Internally within the government, solid legal arguments also strengthen greatly the bureaucratic hands of proponents of force as policy deliberations unfold. During the Cuban Missile Crisis, some senior decision-makers were concerned, for example, about the U.S. appearing as the unjustified aggressor, and this influenced their consideration of whether and how the United States should use force. These factors have grown in importance since the Cuban Missile Crisis in part because the end of the Cold War has revived faith among some Western states in the U.N. Security Council's primacy in managing security crises and because lawyers now play a more powerful role in many states' (including the United States') security and foreign policy agencies.
When military strikes are launched, international law plays a powerful role in either justifying or delegitimizing actions. Widely understood and respected rules and the principles behind them bolster or weaken political and diplomatic arguments for or against military force. Even if the OAS's approval of the quarantine was insufficient to fully satisfy international law regarding force, it demonstrated broad international backing for action and a commitment to pursuing diplomatic solutions – two core principles of the U.N. Charter system. The U.N. Security Council and OAS, both products of international law, were important forums for communicating the U.S. positions to allies and neutral states and refuting Soviet ones, despite that neither of those bodies was capable of resolving the crisis without U.S. military force and secret bargaining.
The lessons here for Iran policy include that the effectiveness of American or Israeli military strikes or threats of force will depend in part on how persuasively they can argue their legal case to global audiences. Some Western states are increasingly – and correctly, in my opinion – of the view that self-defense rules should take account of the extraordinary destructiveness of nuclear weapons, perhaps especially in the hands of terrorists or terrorist-sponsors. But any claim that preemptive strikes are justified against Iranian nuclear sites will undoubtedly be vigorously contested. The United States or Israel can strengthen their legal hand for possible future action by demonstrating good faith exhaustion of diplomatic alternatives. They can also strengthen it by continuing to work through the U.N. Security Council and with the International Atomic Energy Agency to substantiate authoritatively and credibly the threat of Iranian nuclear capability.
More generally, it is a mistake to judge international law by idealistic standards of whether it can either halt Iranian nuclear ambitions or hold back the United States or Israel from taking military action. It is also mistaken to dismiss it as irrelevant to either Iranian designs or American or Israeli decision-making about possible preemptive strikes. Even during – indeed, especially during – standoffs with catastrophic risks, security strategy and international law are inseparably entwined.
This article appears in full on CFR.org by permission of its original publisher. It was originally available here.