Former Defense Secretary Robert Gates warned in 2012 that an attack on Iran “would make a nuclear-armed Iran inevitable. They would just bury the program deeper and make it more covert.” Yes, we could damage the nuclear facilities, but what happens then? “The results of an American or Israeli military strike on Iran could, in my view, prove catastrophic, haunting us for generations in that part of the world,” he added.
Gates, the defense secretary under both Presidents George W. Bush and Barack Obama, was not alone. There is a reason that the United States has not gone to war with Iran before. The overwhelming consensus of military and intelligence officials and experts has been that doing so would be a disaster.
It is worth remembering that the nuclear risks do not just stem from Iran.
“President George W. Bush’s administration concluded that a military strike on Iran’s nuclear facilities would be a bad idea — and would only make it harder to prevent Iran from going nuclear in the future,” former CIA Director Michael Hayden said, also in 2012.
“After you’ve dropped those bombs on those hardened facilities, what happens next?” former Central Command chief Anthony Zinni asked in 2009. There could be catastrophic economic, political and military consequences on a global scale. The nuclear consequences alone should terrify us.
It is possible that U.S. strikes on Iran’s nuclear sites, coupled with Israel’s sustained bombing of Iranian political and economic targets, could cause the Iranian government to collapse, or agree to President Donald Trump’s demand for “unconditional surrender.”
But it is more likely that Iran could race to build nuclear weapons. It could produce enough uranium for the cores of 10 bombs in a matter of days. It is unknown how long it would then take to turn the uranium into metal, shape it into weapons and then assemble it into one or more devices. U.S. intelligence agencies have assessed that it would take a year or more, but Iran could find shortcuts and do it as little as three to five weeks — as China did in 1964.
Iran does not have to create a modern, sophisticated warhead that could fit on the tip of a missile. It could assemble a crude device that resembles the bomb the United States used to destroy Hiroshima 80 years ago. It could put that bomb in a plane, a truck or the belly of a cargo ship and smuggle it into the territory of a U.S. ally, or America itself.
Iran might also explode a bomb in its own deserts, demonstrating that it has now become a nuclear power, and threaten to use it unless Israel and the United States stop their attacks. This would be in addition to other potential actions that officials and experts have long predicted, such as closing the Strait of Hormuz, cutting off one-fifth of the world’s oil supplies and triggering a global recession; attacking U.S. troops in the region; and terrorist attacks on U.S. interests and economic targets around the world.
It is worth remembering that the nuclear risks do not just stem from Iran. Of the three countries involved in this war, two are nuclear-armed nations. If Iranian missiles were to kill hundreds in Tel Aviv, would Israel decide to launch its nuclear-tipped missiles on Tehran? Or if the Iranians sink one of the three U.S. carriers now heading to the region, would Trump cross the nuclear line? We have been fortunate that no nation has used a nuclear weapon in combat in 80 years. This war could end that streak.
Even if the attacks on Iran succeed — if Iranian centrifuges and uranium stocks are destroyed — nuclear risks will multiply.
Iran does not have to create a modern, sophisticated warhead that could fit on the tip of a missile. Nations around the world may conclude that only a nuclear weapon can save them from conventional military attack. Right now, our own European allies worry that Trump’s retreat from fully supporting Ukraine — and budding alliance with Russia — means that if the U.S. nuclear umbrella no longer protects them, then they had better build their own. War with Iran may also be the final blow to the already tottering nuclear nonproliferation regime. President George W. Bush began weakening the nuclear guardrails when he withdrew from the Anti-Ballistic Missile Treaty in 2002 (promising a national missile shield that never materialized), and withdrawing from the 1994 agreement that had blocked North Korea’s nuclear program (now fully developed, including missiles that can hit the United States). Trump and Russian President Vladimir Putin accelerated the disintegration of global nuclear norms by withdrawing from three other agreements. The sole remaining treaty limiting nuclear arms, the New START treaty, expires next year with no replacement in sight. This war could cause many countries in Europe and Asia to conclude that they must pull out of the Nuclear Non-Proliferation Treaty, ending five decades of nuclear restraint. We would be plunged back into the nuclear anarchy of the 1950s and 1960s when dozens of countries had nuclear weapons programs. These are the kind of “possible unintended consequences of a strike” that former Chairman of the Joint Chiefs Adm. Mike Mullen warned about in 2009. Yet, we have had nothing like the sustained, serious debates that accompanied previous Iranian crises. Trump acts alone, ignoring advice and the Constitution to decide if he “may or may not” attack. With three unstable, unpopular leaders facing off, the stakes could not be higher, the consequences more unpredictable. We are rolling the nuclear dice. This is unlikely to end well.
Joseph Cirincione
Joseph Cirincione is the vice chair of the Center for International Policy Board of Directors. 
