If he should win re-election, US President Barack Obama will likely reaffirm his oft-declared goal of a "nuclear-weapons free world." Although this objective will resonate pleasingly with all who "seek peace," it is both unattainable and undesirable. Moreover, in the particular case of Israel, a close US ally, any "successful" regional or worldwide denuclearization could open the doors to catastrophic enemy aggressions.Here, such aggressions could even be irremediable.Mr. Obama still misses the main point. Serious strategic understanding is sometimes counter-intuitive. The core instabilities of world politics are never due to the presence or absence any single kind of weapon system. This includes those systems which may exhibit a seemingly limitless potential for destruction. The writer (Ph.D., Princeton, 1971) is the author of many books and articles on nuclear strategy and nuclear war, including several of the very first works on nuclear terrorism. His writing has appeared in Special Warfare and Parameters, publications of the US Department of Defense, and also in International Security (Harvard); World Politics (Princeton); The Israel Journal of Foreign Affairs; and International Journal of Intelligence and Counterintelligence. In Israel, he was Chair of Project Daniel (PM Sharon, 2003). He is the author of Apocalypse: Nuclear Catastrophe in World Politics (University of Chicago Press, 1980), and Security or Armageddon: Israel’s Nuclear Strategy (Heath/Lexington, 1986). Professor Beres was born in Zürich, Switzerland, on August 31, 1945.In essence, global fragility is not about failing to harness certain prominent powers of annihilation. Rather, it is the palpable result of assorted national and terrorist leaders who may convincingly promise cooperation and coexistence, but, in reality, dream lasciviously of corpses. Most worrisome of all are those readily identifiable enemy leaders who might sometime combine diplomatic recalcitrance and nuclear capacity with full-blown irrationality. As Israel especially may soon need to learn, it is not necessarily impossible to deter irrational adversaries, even nuclear ones. But it is first necessary to understand their particular preferences, and also their specific rank-orderings or hierarchies of these preferences. It follows that such a critical understanding must become an utterly primary objective of any U.S. strategic doctrine.For effective purposes of strategic deterrence, irrational does not mean "mad" or "crazy." It suggests only a conceivable and possibly expected willingness to subordinate national survival to some other preference, or combination of preferences.In this connection, Americans and Israelis now rightly fear a nuclear Iran that is led by just such irrational decision-makers. By themselves, the American president should fully understand, nuclear weapons are not the real problem. In general, weapons are never more or less destabilizing simply because of their inherent capacity to destroy. Nuclear weapons are neither innately good, nor innately evil. In certain cases, most obviously Israel, they can provide a credible basis for viable deterrence. In such not necessarily residual cases, moreover, nuclear weapons can actually serve as vital impediments to war.Instead of naively and mistakenly seeking “a world free of nuclear weapons,” the president of the United States should now be working determinedly toward a very different objective. This is a world that would be substantially freer of all-too-ready enemy inclinations to "total war," or to mega-terror. To accomplish this goal, he should now be focusing energetically on fashioning an improved and more visible US strategic doctrine.I refer to a carefully codified plan for national security that would deal capably not only with various Jihadist adversaries, both state and sub-state, but also with prospective and still-formidable foes in Russia, North Korea, China, Iran, and possibly even a post-coup Pakistan. This very same primary obligation falls directly upon the shoulders of the Republican candidate for president. Until now, and for whatever reason, Mr. Romney has failed to confront this country's most salient security threats with any degree of strategic sophistication or intellectual seriousness. “Our national nuclear strategy is a bipartisan problem.”America needs an appropriately refined strategic doctrine to deal with certain persisting threats of war and terrorism. But, blindsided by unwarranted and misconceived nuclear hopes, and also by corresponding diplomatic fictions (e.g., the presumed efficacy of New START with Russia, and the multilateral Nuclear Non-Proliferation Treaty, or NPT), this president has yet to create a coherent policy framework from which certain particularly needed operational options could be quickly and suitably derived.Barack Obama has come late to this issue. For his part, Mitt Romney has yet to even mention the need for such an indispensable policy framework.Whether we like it or not, history has certain non-dismissible meanings. During the 1950s, the United States first began to institute various doctrines of nuclear deterrence. At that time, the world was tightly bipolar, and the enemy was the Soviet Union. American national security had been openly premised on a strategic policy called “massive retaliation.” Over time, especially during the Kennedy years, that stance was modified by something we then called “flexible response.” Today, a far more complex world reveals multiple and inter-penetrating axes of potentially violent conflict. There are almost four times as many countries as had existed in 1945. In this expressly multipolar world, Russia, which had earlier assumed diminished importance in American strategic calculations after the fall of the Soviet Union, is again an authentic security concern. Russia’s leaders have issued belligerent declarations on the resumption of Russian long-range bomber flights, and on corollary Russian intentions to expand production of intercontinental ballistic missiles. Presently, Russian nuclearization proceeds with nary a nod of respect for President Obama’s high-minded stance on “a world free of nuclear weapons.” Quite the contrary.Among other things, the Russians are spurred on in their ambitious nuclear invigorations by an entirely understandable fear of planned US ballistic missile defenses in Europe. Such active defenses, in the Russian view, threaten the unassailable and mutually agreed upon deterrence logic of "mutual vulnerability." Oddly enough, it appears that both Obama and Romney presently favor a futile and ultimately destabilizing expansion of American missile defenses.So, what should America do about nuclear weapons? This is the single most important question that needs to be asked, by the incumbent president of the United States, and also by his Republican opponent. Unless they can both answer this existential question satisfactorily, and quickly, nothing else in their respective platforms may matter at all.There are answers. It is high time to gather together this country’s best strategic thinkers, and put them to work on a present-day equivalent of the Manhattan Project. This time, however, the task would not be to develop any new form of super weapon. Still, it should not be seized upon as a narrowly propagandistic opportunity to oppose nuclear weapons across the board. After all, without a nuclear "balance of terror" during the Cold War, there would likely have been a third world war.Among other things, an American strategic "brain trust" will need to consider controversial matters of nuclear targeting. These issues would concern certain basic differences between the targeting of enemy civilians and cities (“countervalue” targeting), and the targeting of enemy military assets and infrastructures (“counterforce” targeting). To be sure, most Americans don’t yet realize that the essence of “massive retaliation” and MAD had been countervalue targeting. Nonetheless, in those relatively promising circumstances where enemy rationality might still be reasonably assumed, robust and reliable US deterrence could once again require recognizable countercity targeting.At a time when our sitting president draws his fundamental strategic policy options from idealized and erroneous assumptions about nuclear disarmament, and when his Republican opponent ignores complex national defense subjects altogether, all Americans need to understand that they are at a renewed risk of unprecedented enemy attacks. This is assuredly not the time for Americans to debate the plain foolishness of a "nuclear weapons free world." It is time to fashion an informed, nuanced, and verifiably capable US strategic doctrine. This task will have to address several still-impending prospects for preemption ("anticipatory self-defense," in jurisprudential terms), as well as greatly improved methods of distinguishing adversaries (state and sub-state) according to whether they are presumed rational, irrational, or “mad.” It will also need to include certain more-or-less related elements of nuclear deterrence, active defense, and cyber-warfare.It is the principal function of strategic doctrine to cast light in dark places. To gather the needed sources of illumination, both candidates for president should finally begin to clarify their respective positions on nuclear weapons and US national security. In any event, it is irresponsible to simply oppose such weapons across the board (Obama), or to ignore the underlying issues altogether (Romney).For Israel as well as the United States, any such irresponsibility could bode very badly for national security.