Associated Press

For all of the uncertainty of the Trump administration’s nearly three years in power, genuine international crises have been rare. That’s changing right now. The attack a week ago on Saudi Arabia’s massive Abqaiq oil field took offline half of the country’s oil production—some 5 percent of global output. The drone and missile salvo has the hallmarks of Tehran, and with top administration officials pointing to Iranian culpability, the world is watching to see if and how the United States responds. It’s the most dangerous moment of Donald Trump’s presidency thus far.

Not so long ago, a devastating attack on Saudi oil supplies would almost certainly have elicited an American military response. Ensuring the continued flow of energy from the Middle East was widely seen as crucial, one of the vital American interests that nearly all policy makers believed worth defending. Fracking and reduced U.S. dependence on Middle East oil, the exhaustion and caution borne by two decades of American wars, a new focus on great-power competition, and the complexities of recent diplomacy with Iran have changed all this to a degree.

But only to a degree. Oil prices spiked after the Abqaiq attack, and while they have settled down for now, a new assault could roil them again and harm the American economy. The U.S. defense of Gulf allies, while enshrined in no mutual-defense treaty, has been a general feature of America’s approach to the region since at least the Gulf War. The attack on crucial Saudi infrastructure was inarguably the kind of military aggression Washington wishes not to see repeated. And it followed a summer of hostile actions against tankers in the Gulf of Oman and the shooting down of an American drone.

Thus far, the administration has responded mildly. It has increased sanctions on Iran, but since economic strangulation likely prompted the Iranian attack in the first place, it’s hard to see how a few more sanctions will stop new aggression. It is dispatching troops to Saudi Arabia, but the Pentagon is careful to note that they will be there only in a defensive capacity. This, too, is unlikely to change Iranian behavior.

Some U.S. experts have talked up the mostly forgotten Operation Praying Mantis, when in 1988 the United States responded to Iran’s mining of the Persian Gulf by destroying at least half of the country’s navy. Others propose cyberattacks, covert operations, or attacks on Islamic Revolutionary Guard Corps forces in Syria. The leadership in Tehran, for its part, appears to see Trump as something of a paper tiger, a president fond of sanctions and heated rhetoric but one who would withdraw from the Middle East rather than risk getting stuck there. For Trump, who rails against the waste of American blood and treasure in Iraq, the reality of Iran’s population (more than three times bigger than Iraq’s in 2003), its military and reserves (both larger than Saddam Hussein’s), and its proxies (strewn from Lebanon to Yemen, with American troop installations interspersed) must weigh heavily.

The crux of Trump’s problem is that all of his real options are bad. He could retaliate militarily, risking a wider war with Iran and its proxies. He could back down, inviting even more aggressive Iranian actions—unless he goes far further and abandons his pressure campaign entirely (which he has never suggested he’ll do). The president’s goals of getting ever tougher on Iran and extricating America from the Middle East are in fundamental tension.

So: Strike back, and risk war now. Don’t strike back, and risk war later.

Examining the question in light of the Islamic Republic’s history, the stronger case is for a move now, possibly in a unilateral strike on Iranian assets or a Saudi strike backed by the United States. But while an attack on, say, cruise-missile depots, launchers, drone facilities, or oil fields—or a covert operation whose author becomes plain—may be necessary to restore deterrence, it is far from sufficient. Crucially, the Trump administration must clarify the objectives of its Iran policy and the point of its pressure campaign.

It’s been a cacophony. Trump talks about one-on-one diplomacy with Iranian President Hassan Rouhani and the possibility of a bilateral treaty that would improve on Barack Obama’s nuclear deal. The secretary of state has issued 12 demands that go well beyond the nuclear file to include Iranian support for militant groups in the region. Until his departure as national security adviser, John Bolton seemed bent on regime change. While all can agree on pressure as a tactic, it is entirely unclear what Tehran must do to achieve a relaxation.

Over the weekend, senior Trump officials described the administration’s policy as a success, providing as evidence the harm it has done to the Iranian economy. Such an approach confuses means with ends. Clarifying the ends is crucial. Included in them, one would imagine, would be avoiding the kinds of attacks that have devastated Saudi Arabia’s oil fields. Better to figure out what precisely the United States wants, and how it wishes to elicit it, before launching a strike to punish Tehran’s transgression.

Of course, it’s possible all this could pass, like so much ferment in a hot summer. Retaliation could end the cycle of violence. Or a nonresponse could do so. Both are unlikely. It’s far more plausible that Trump will be confronted with more instability and tough choices—precisely in the place and at the time he wants them least.

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