It takes neither  unique intellectual brilliance nor supernaturally honed intuitive skills to predict the consequences of hazardous foreign-policy moves.  On numerous occasions over the past decade and a half, I have advised against U.S. military interventions not because of my visceral isolationist zeal, but because I deemed the consequences of those actions to be contrary to the interests of this country and its people, viewed through the “realist” prism.  Will support for the Muslims in Bosnia buy us any brownie points in the Islamic world at large?  Cui bono from bombing Serbia?  What is the definition of “victory” in Afghanistan, or in Iraq?  Is Qaddafi really worse—as far as our security and energy interests are concerned—than his foes?

Being proved right is no cause for satisfaction, however, because the foreign-policy “community” in Washington, D.C., does not learn from its mistakes.  Its key players behave like lunatics whose failures inspire them to redouble their efforts.  Some of them are clamoring—yet again—for war with Iran, although there is no new evidence that Iran is pursuing a nuclear-weapons program.  Claims that Tehran is doing so were first made a quarter of a century ago by Jane’s Defence Weekly, which went so far as to predict that Iran’s first nuclear weapon would be ready within two years.

The Iranians are undoubtedly enhancing their enrichment capability and seeking control of a full nuclear-fuel cycle, but there is nothing in the recent International Atomic Energy Agency’s report to indicate that they are building a bomb.  Nonetheless, the drumbeat has returned to Washington, and its objective is to present a military attack against Iran as a legitimate policy option to deal with a major threat to the United States.  This campaign is reminiscent of the propaganda barrage over the 18 months preceding the war against Iraq in March 2003: It is based on an exaggerated threat and on the bogus claim that diplomatic solutions have been exhausted.

Let us look at the realist argument against a war with Iran.

The question that needs to be asked first is not whether Iran is developing a nuclear weapon—let us assume that this is a documented fact, though it is not—but whether an Iranian bomb would be a threat to the United States.  What are the purposes of the Iranian decisionmakers?  To threaten Europe, thus necessitating an American antimissile shield along Russia’s western borders in Central Europe?  To threaten the United States even, regardless of a guaranteed hundred-fold retaliation to any attack?  Or to protect Iran from what her leaders perceive to be a threatening environment?

Iran has one neighbor to the west and another to the northeast who were both invaded by the United States over the past 11 years.  It is clear that neither Afghanistan nor Iraq would have been invaded had her leaders actually possessed weapons of mass destruction.  Iran’s eastern neighbor is Pakistan, an unstable and unpredictable nuclear power.  In the wider neighborhood there are two other key players with an atomic arsenal, India and Israel, with Turkey not far behind.  Under the circumstances, having an independent nuclear deterrent is a perfectly rational option for the government in Tehran to pursue—any Iranian government, Islamist or secular, monarchist or republican, pro- or anti-Western.  That option is based on the realities of the security equation and not on the millenarian zeal of Shi’ite fanaticism or on genocidal Jew-hatred, as the proponents of war would have us believe.  It is ironic that our Nobel laureate President is seemingly unable to grasp the realpolitik of the Iranian bid for the bomb and prefers to parrot George W. Bush’s mantra that “all options” must remain open.

Even if Iran were to garner an arsenal of a dozen devices, which would take a decade at least, the overall strategic balance would remain fundamentally unaltered.  Indeed, the political climate in the region may actually improve: Iran would feel safe from an American attack and therefore at least potentially less likely to indulge in destabilizing proxy interventions in the region.  Needless to say, the Iranians would not be tempted to place their hard-won nuclear arsenal at the disposal of their militant Arab clients, such as Hezbollah in Lebanon.  Israel may have reason to feel threatened by Iran’s long-term plans, but it is up to Israel to consider her options and to act accordingly.  She may well decide on a robust response, like her bombing of the Osirak nuclear plant in Iraq in 1981, with all the attendant risks and uncertainties.  She should not expect the United States to do the job on her behalf, however.

The Saudis would also feel uncomfortable with a nuclear-armed Iran across the Gulf, and that would be a good thing.  The more the unspeakable kleptocracy in Riyadh focuses on potential threats in the neighborhood, the less likely it is to escalate its global proliferation of Islamic extremism, which it has lavishly financed for decades.  In any event, as the example of North Korea shows, the possession of the bomb by a single actor does not necessarily lead to a sudden nuclear rush in the region.

The second objection is technical.  Regardless of its formal or substantial justification, can a U.S. war against Iran be kept limited and winnable?  The initial intent may be to execute bombing raids against a dozen or perhaps two-dozen specific targets, but would that merely set Iran’s efforts back by two or three years?  And what if Iran retaliates by mining the Straits of Hormuz, destroying vulnerable oil installations in the Emirates and Saudi Arabia with her arsenal of Scuds, and detonating dirty bombs in downtown Tel Aviv and midtown Manhattan?  In other words, what if the Iranians treat a U.S. attack not as a limited action that, in the War Party’s calculus, would produce a limited response, but as an existential struggle comparable to Khomeini’s all-out reply to Saddam’s attack 30 years ago?

If the Iranians respond forcefully, the advocates of limited air strikes against nuclear installations are certain to demand troops on the ground, regardless of risks and consequences, because our “credibility” would be at stake.  In reality, America’s credibility would be terminally undermined by the resulting Iranian quagmire.  An all-out “Operation Iranian Freedom” is not a rational option, because even with our unsurpassed military capabilities, the United States would not be able to mount a full-fledged invasion.

The third predictable consequence of a U.S. attack on Iran would be the reigniting of the war in Iraq.  Pretending that the leaders of Iraq’s Shi’ite community are a decent and friendly lot has been a key element in the U.S. exit strategy.  An onslaught on their coreligionists would prompt a Shia uprising in Iraq—led by the likes of Muqtada al-Sadr but more or less covertly supported by the government of Nouri al-Maliki—at a time when the withdrawing U.S. forces would be vulnerable to insurgent attacks and unable to secure quick reinforcements.  The resulting debacle would necessitate either a comprehensive reoccupation of Iraq with hundreds of thousands of American troops costing hundreds of billions of dollars or, more likely, a humiliating, Saigon-style retreat from the shrinking Green Zone in Baghdad.  Furthermore, the sympathy with the victims of the Great Satan’s attack would spread to the Arab Street all over the region, potentially undermining the stability of U.S.-friendly regimes in Bahrain and the Emirates.

The fourth consequence of a war against Iran would be a global economic meltdown of unprecedented severity and magnitude.  Not only would Iran’s output of some four million barrels per day be halted, but the maritime traffic through the Straits of Hormuz, through which most of the oil from the Gulf passes on its way to the Far East and Europe, would come to a standstill.  The resulting global energy crisis would make the aftermath of the Yom Kippur War pale in comparison, pushing a barrel to $300 within weeks and making the economic and financial crises of the past three years in Europe and the United States seem like the good old days.

The fifth consequence of such a war would be internal consolidation of the Iranian regime, a calcified theocracy devoid of ideas and solutions as it faces economic stagnation and political tensions.  Domestic squabbles and the infighting of recent months would be forgotten, and any sign of opposition to the regime would be equated with treason.  There would be no Iranian Spring for decades to come.  On the other hand, without the unifying effect of an external threat, the mullahs’ regime may yet prove more vulnerable to implosion than we would otherwise suspect.

Instead of plotting a military action against Iran with no clear exit strategy at a prohibitive cost to our core interests, Washington would be well advised to prepare a strategy for dealing with Iran as a nuclear power.  Deterring and containing Iran would be easier than deterring and containing the Soviets 50 years ago.  The country’s regime, admittedly unpleasant, is neither suicidal nor tainted by the blood of untold millions, as the two communist nuclear powers were.  If the Iranian government considers itself threatened by the United States, the solution is to try bilateral diplomacy based on an offer of U.S. security guarantees to Iran in return for a rigorous supervision regime and a formal pledge that Iran refrain from developing nuclear weapons.  The Obama administration should make a direct approach to Tehran.  A reasonable agreement would also allow Iran to enrich uranium to the extent needed for power generation and accept Iran’s right to the enrichment technology, so long as she agrees to subject her entire nuclear program to international oversight.

It is noteworthy that the United States has never suggested subjecting Israel to the same standard of antiproliferation scrutiny that is applied to other aspiring nuclear powers.  This implicit hypocrisy is not sustainable.  Following the disintegration of the Soviet Union 20 years ago, the strategic rationale for U.S. micromanagement of Middle Eastern affairs disappeared.  America should devise and conduct regional policies based on her own objectives and her own security calculus.  Successive U.S. administrations have been unable to do so for decades, however, allowing influential interest groups to have a decisive say in defining U.S. policy in the greater Middle East.  The price of converting regional strategy into another form of domestic politics has been high.  It has included two wars with Iraq and an open-ended quagmire in Afghanistan.  America can ill afford to add the war in Iran to the list, and it is not in the American interest to do so.