WASHINGTON – If diplomacy with Iran fails, the United States will be left with only two options: deterrence and preventive war. Of these policies, deterrence is the "least bad," asserts a study released today by the Cato Institute. In the policy analysis "The Bottom Line on Iran: The Costs and Benefits of Preventive War versus Deterrence," Justin Logan, foreign policy analyst at the Cato Institute, systematically analyzes the short- and long-term consequences of both deterrence and preventative war, demonstrating that the costs of military action in Iran would be nightmarish.
Despite hawkish claims to the contrary, "delaying Iran's nuclear program is the only conceivable benefit" that could likely be derived from a policy of striking Iran's nuclear sites, asserts Logan. Such a move would be unlikely to prevent the Iranians from eventually acquiring a nuclear capability, and instead serve to foment anti-American sentiment throughout the Muslim world, while consolidating the mullahs' power and undermining liberalization inside Iran.
A number of problems complicate the prospect of a preventive war on Iran. The U.S. appears to have poor intelligence on Iran: little is known about its nuclear sites and the extent of its nuclear program, and what information we do have is highly disputed. Escalation of the conflict is virtually assured; counterstrikes are likely, in Iraq and the broader Middle East, as well as possibly even inside the U.S.
Logan concedes that deterring a nuclear Iran "raises a host of undesirable consequences," and that a major caveat of any deterrence policy is the question of whether the Iranian leadership is rational. However, he assesses the regime's behavior in previous strategic situations, and notes that "despite how they may appear to Western eyes, the clerics are rational, deterrable actors."
Examining the negative consequences that a deterrence policy could create, including an emboldened Iran, the ensuing regional response, and the undermining of American and Israeli influence in the Middle East, Logan acknowledges that such concerns are valid, yet overstated. He notes "while a nuclear capability would take 'regime change' off the table, it would not give Iran carte blanche to act as it pleases with respect to all of its foreign policy goals."
To counter the danger a nuclear Iran may pose, Logan recommends increased communication to delineate "red lines" that should not be crossed, and to keep the lines of communication open, however unpalatable this may seem. "Deterrence is not 'satisfying,' in that it does not produce a decisive outcome quickly," he concludes. "But neither, in this case, would preventive war."
Policy Analysis Paper no. 583: https://www.cato.org/pub_display.php?pub_id=6790