Joshua Roberts / Reuters

My colleague David Frum, a supporter of the Iraq War who coined the phrase axis of evil, issued a warning in a column this week: “The project of a war with Iran is so crazy, it remains incredible that Donald Trump’s administration could truly be premeditating it,” he wrote. “But on the off, off chance that it is, here’s a word of caution from a veteran of the George W. Bush administration: Don’t do it.”

Among the reasons he offers:

The U.S. would find itself without allies except for Israel and the Gulf states. The Trump administration would find itself even more isolated politically at home. Most Americans do not support, trust, or respect Trump’s leadership.

There is no Colin Powell–like figure in this administration, no senior official who commands respect across party lines. Pitifully few people in this administration command respect even within party lines. The administration’s record of casual incompetence at minor tasks raises terrifying questions about its capacity for a gigantic undertaking like a land war against a Central Asian state.

My colleague James Fallows, an Iraq War opponent who wrote “Blind Into Baghdad,” the inside story of a historic failure, declared this week, “Military engagement with Iran would be far stupider, more reckless, and more destructive.” As he observed after watching an Iran-focused war game in 2014:

Unlike Saddam Hussein’s Iraq, a threatened Iran would have many ways to harm America and its interests. Apart from cross-border disruptions in Iraq, it might form an outright alliance with al-Qaeda to support major new attacks within the United States. It could work with other oil producers to punish America economically. It could, as [Marine Corps Colonel Thomas X.] Hammes warned, apply the logic of “asymmetric,” or “fourth-generation,” warfare, in which a superficially weak adversary avoids a direct challenge to U.S. military power and instead strikes the most vulnerable points in American civilian society, as al-Qaeda did on 9/11.

If it thought that the U.S. goal was to install a wholly new regime rather than to change the current regime’s behavior, it would have no incentive for restraint.

My colleagues aren’t alone in worrying that a disastrous war with Iran is a possibility. Last year, Trump withdrew from the nuclear deal negotiated during the Obama administration and imposed punishing sanctions on the country. Last month, testifying before the Senate Foreign Relations Committee, Secretary of State Mike Pompeo refused to acknowledge that waging war against Iran is not covered by the September 2001 Authorization to Use Military Force, which Congress passed in response to the 9/11 terrorist attacks.

This week, the Department of Defense unveiled an updated military plan that “envisions sending as many as 120,000 troops to the Middle East should Iran attack American forces or accelerate work on nuclear weapons,” The New York Times reported. “On Tuesday,” the newspaper added, “Spanish defense officials withdrew a Spanish frigate that was part of an American-led carrier strike group heading to the Persian Gulf, to avoid entanglement in any upcoming conflict.” The State Department has just evacuated some of its staff from Baghdad. And Fox News is hyping alleged ties between Iran and al-Qaeda.

In Congress and the press, the prospect of war with Iran is being treated as more worrisome than recent U.S. actions in Syria, Yemen, Libya, Somalia, and beyond, a posture that makes sense, given the likely costs of fighting that country.

Yet the relative apathy that surrounded those smaller conflicts—in Congress, the media, and the public—is a factor that makes a conflict with Iran more likely.

Picture this alternative reality:

Imagine that President Barack Obama had been greeted with massive street protests when he waged war against Libya; that favoring that intervention had prevented Hillary Clinton from advancing past the Democratic primary; that the critics now threatening Trump with impeachment had cited his missile strikes on Syria as prominently as the claim that he obstructed justice; that the Democratic presidential candidates were excoriating Trump more for complicity in Saudi Arabia’s dirty war in Yemen; and that street protesters were pressuring the White House with calls for the return home of all U.S. troops.

In this counterfactual universe of furious opposition to waging any war unlawfully, or launching any new wars of choice without demonstrating their necessity, Trump would be less likely to let hawks risk, let alone provoke, a major war. It is conceivable that he wouldn’t have appointed the hawks in the first place, or that he would have long ago fired them or reined them in to offset their political cost. It is certain that anti-war voices would have mobilized earlier, in greater numbers, to speak out against the very first steps toward war with Iran.

Instead, doves in the White House were left to make speculative cases that war would hurt Trump politically rather than being able to point to a large anti-war faction, and significant backlash is coming only after a long series of needless escalations.

The dearth of an anti-war movement may even have delayed Trump’s efforts to oppose his hawkish advisers––he reportedly said this week that he doesn’t want war, according to an article that The New York Times published yesterday.

Let all this be a lesson.

The best insurance against a catastrophic war of choice, now and going forward, is a permanent anti-war movement that opposes all illegal or imprudent wars, insisting on public debates and congressional votes, no matter how small the conflict. If Americans attempt to mobilize against only the biggest, dumbest wars, they will not get organized until it’s too late to stop some of them.

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