Unhindered by the flagrantly contrived diplomacy launched recently in Washington, Tehran now marches unhindered to full nuclear weapons status. When this condition is finally achieved, any American rapprochement with new Iranian President Hassan Rouhani notwithstanding, Israel and the United States will desperately try to contain a long-anticipated atomic menace. Asymmetrically-sized, but more-or-less jointly imperiled, the two allied states will then seek to identify still-available remedies. In essence, this compensatory default position will center on instituting a dependably stable system of nuclear deterrence. To be sure, any such residual effort by Washington and Jerusalem would be well-intentioned and indispensable. After all, to avoid a possible future of near-measureless lamentations, these allies would need to reconstruct certain earlier core elements of "Mutual Assured Destruction." MAD, of course, was the nuclear threat-based scheme that had successfully preserved superpower peace during the US-Soviet Cold War.LOUIS RENÉ BERES was educated at Princeton (Ph.D., 1971), and is Professor of International Law at Purdue. Born in Zurich, Switzerland, on August 31, 1945, he is the author of many major books dealing with nuclear strategy and nuclear war. In Israel, he was Chair of Project Daniel (2003). Professor Beres is a frequent contributor to The Jerusalem Post.Moreover, already back in 1995, David Ivry, then director-general of the Ministry of Defense (later, Israel's Ambassador to the United States), had openly referred to MAD "as a model for Israel."Will this eleventh-hour "containment" effort work? Admittedly, it would seem odd to wax nostalgic about the Cold War, but, in retrospect, that protracted standoff between "two scorpions in a bottle" (Manhattan Project physicist J. Robert Oppenheimer's famous metaphor) may soon look relatively benign. At that time, after all, the two dominant national players did share an overriding commitment to stay "alive." Then, both sides were prudentially disposed to "coexistence."Each side, from the 1950s until the early 1990s, when the Soviet Union rapidly imploded, was predictably "rational."Rationality remains a key factor in deterrence logic. More precisely, in order to be sustained in world politics, any system of deterrence must be premised on an assumption of rationality. This means that each side must consistently believe that the other side will value its continued national survival more highly than any other preference, or combination of preferences. In the Cold War era, rationality proved to be an indisputably reasonable and consistently correct assumption. Now, however, we may have good reason to doubt that MAD could work as well in the Middle East, as it did during the Cold War. Conceivably, a nuclear-endowed Jihadist regime in Tehran might not be willing to maintain the same stable hierarchy of national preferences. Even though Iran's new president sounds substantially less inflammatory than his predecessor, it is still the Grand Ayatollah who will be authorizing the most critical or existential national decisions.Over time, of course, the principal decision-makers in Tehran could turn out to be just as rational as the Soviets were. Still, there is certainly no way of knowing this for sure, or, for that matter, of predicting Iranian rationality with any previously-tested bases of reliable judgment. Mathematically, moreover, there is no acceptable way to ascertain the probability of unique events, and an Iranian leadership that could deliberately slouch toward nuclear apocalypse is not discoverable in any modern history.This brings up the most sobering question of all. What if there should be no preemption against Iran, and if any consequent nuclear deterrence should fail to prevent war between Iran and Israel? What, exactly, would happen, if Tehran were to actually launch a nuclear Jihad against Israel, whether as an atomic "bolt from the blue," or, as a result of escalation, either deliberate, or inadvertent? In considering this most basic question, it must be kept in mind that even a fully rational Iranian adversary could sometime decide to launch against Israel, because of (1) incorrect information used in its vital decisional calculations; (2) mechanical, electronic, or computer malfunctions; (3) unauthorized decisions to fire in the national decisional command authority; or (4) coup d'état.Almost thirty-five years ago, I published the first of many subsequent books that contained informed descriptions of the physical and medical consequences of a nuclear war. These descriptions were focused generically on any nuclear exchange, and were extracted primarily from a respected 1975 report issued by the National Academy of Sciences. Although they were not generated with any particular reference to the Middle East, these core expectations were universally applicable, and not in any way geographically specific.In essence, after suffering an Iranian nuclear attack, normal human society in Israel would come to a complete halt. As Americans experienced and witnessed with Hurricane Katrina, basic mechanisms of civil order can be torn away from a large US city by a “mere” storm in less than 24 hours. Of course, in any serious comparison with tangible nuclear attack effects, the New Orleans natural weather catastrophe was plainly “minor.” In New Orleans, suffering residents could still count upon assistance from an unaffected and centralized (federal) government authority (FEMA), as well as from several private aid agencies.A nightmarish nuclear attack scenario would not even need to be considered if Iran could still be kept distant from atomic weapons. Barring the increasingly unlikely prospect of an eleventh-hour preemption against Iranian hard targets, however, it will become necessary to implement a stable and conspicuous program of regional nuclear deterrence. With this particular threat program in place, Israel could be allowed to identify any still-remaining options for deterring both rational and irrational decision-makers in Tehran.Although, by definition, irrational Iranian adversaries would not value their own national survival most highly, they could still maintain a determinable and potentially manipulable ordering of preferences. It follows that Washington and Jerusalem should promptly undertake to anticipate this expected ordering, and to fashion all corollary deterrent threats accordingly. It should also be borne in mind that Iranian preference-orderings would not be created in a vacuum. Eventually, assorted strategic developments in "Palestine" and elsewhere in the region could impact such orderings, either as "synergies," or - in more expressly military language - as "force multipliers." In the best of all possible worlds, Israel and the United States would never have permitted Iran to reach these penultimate stages of nuclear weapons development, stages that now involve not only uranium enrichment, but also the feasible production of bomb-grade plutonium. But this is not the best of all possible worlds, and it is therefore immediately incumbent upon both Jerusalem and Washington to set the foundations for reliable nuclear deterrence in the Middle East. Without yet discounting a preemption option altogether, both countries, singly and in collaboration with one another, should now focus upon certain urgently necessary final security measures. These measures would intend to ensure that Iran's leaders could never calculate a nuclear aggression against Israel to be gainful or cost-effective. Among other things, including budgeted continuance of Israel's Arrow-3 ballistic missile defense (BMD) program, this would mean a partial and selective end to the country's longstanding policy of “deliberate nuclear ambiguity." Soon, in order to enhance the critical persuasiveness of its indispensable nuclear deterrent, Israel will have to remove its alleged "bomb in the basement." The point here would not be to reveal the obvious - that is, that Israel merely has the bomb - but rather to communicate to all prospective adversaries that its nuclear forces are usable (not too destructive), well-protected, and fully capable of penetrating any nuclear enemy's active defenses.