Louis René Beres is the author of many books and articles dealing with international relations and international law and is a professor at Purdue University.
From the beginning of the nuclear age, deterrence has rested squarely upon assumptions of rationality. But what, exactly, is meant by "rationality," and does present-day Iran really meet this expectation?
Recently interviewed on CBS's 60 Minutes, Meir Dagan, former chief of Israel's Mossad, stated: "The regime in Iran is a very rational one." Moments later, however, Dagan hedged a bit, indicating that it was "not exactly our rational," and that Ahmadinejad was "not exactly rational based on Western thinking." In essence, Dagan was saying only that Iran's leadership displays "logical thinking." There was nothing in his remarks to suggest that this regime would consistently value national survival as its very highest goal.
Ideally, therefore, Iran would still be prevented from becoming a nuclear weapons state. After all, even if we can accept Dagan's particular assessment of Iranian rationality, that country's prospective nuclear force commanders might still sometime choose to value certain preferences more highly than national self-preservation. Such a scenario of failed nuclear threat dynamics is improbable, but it is surely not inconceivable.
For several tactical reasons, the remaining prospect of any operationally viable pre-emption options for Israel and/or the United States is dimming quickly. This requires, especially for Israel, heightened preparations for active antimissile defenses. It will also require, contrary to a prevailing notion that "irrational" adversaries cannot be deterred, the implementation of certain new forms of deterrence.
What does this mean? Irrationality is not the same as madness. Unlike a "crazy" or "mad" adversary, which would have no discernible order of preferences, an irrational Iranian leadership might still maintain a distinct and consistent hierarchy of what it wishes. The top of this hierarchy would be represented by certain clear and widely held religious values and sites.
Although such a leadership might not be deterred by more traditional threats of military destruction—because a canonical Shiite eschatology could actually welcome "end times" confrontations with "unbelievers"—it might still refrain from attacks that could elicit harms to its religious values. Obviously, Iranian concern for safeguarding the holy city of Qom should come immediately to mind.
It is also plausible that an Iranian leadership could simultaneously value certain of its core military institutions, and would also be deterred by credible threats to these institutions. A prime consideration would be the Iranian Revolutionary Guard Corps, the power behind the Iranian dictatorship, the principal foe of the Iranian people, and the current leadership's main instrument of repression. Here, it would be purposeful for Washington or Jerusalem to hold at risk the Guard's physical facilities, its terrorist training camps, its navy of small attack boats, its missile program, the homes of its leaders, and its space program. To be excluded from Israeli and American-generated vulnerabilities, however, would be most civilian targets, and also those military targets which are not identifiably Guard-related.
A nuclear Iran would be dangerous to Israel and the United States even if its leadership were, in fact, entirely rational. After all, miscalculation, or errors in information, could still lead a perfectly rational adversary to strike first. In these circumstances, even the very best antimissile defenses would be inadequate.
This is because such defenses would require a near-100 percent reliability of intercept to be useful for any "soft-point" protection of cities; this extraordinary degree of reliability could never be reasonably expected. In such systems, there would always be too much "leakage."