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There was palpable relief in US foreign policy circles this month when the US launched missiles at Syria. Many observers welcomed it as evidence that the US remains willing to use its military to send messages to foreign leaders and defend international norms.

Some welcomed it as a sign that President Trump, despite his bluster, could be persuaded to act in line with standard American practices. And the fact that many people had both reactions at once shows how deeply entrenched the idea of military intervention is in conventional US foreign policy thinking.

A remarkable coalition emerged to tweet and write op-eds in support of the strikes. Senate Minority Leader Chuck Schumer found himself on the same side as House Speaker Paul Ryan, sharing company with both Sean Hannity from Fox News and Ana Navarro on CNN. This is remarkable not only because it included members of both parties, many of whom are normally appalled by Trump and his intuitions, but also because it brought together people who under other circumstances are stalwart defenders of international law.

The mix of law, politics, and American exceptionalism that motivates US military intervention abroad has evolved to the point where it unites neocons and liberals, Republicans and Democrats. It forms the taken-for-granted common sense that animates US foreign policy. But this “common sense” has not served the US well.

For liberals and conservatives alike, the appeal of using the US military to respond to mass killing outweighs concerns about breaking the UN Charter’s rules on war (which outlaw wars except as authorized by the Security Council or are justified by individual or collective self-defense, neither of which fit this case).

Anne-Marie Slaughter neatly encapsulated the tension when she said the US attack “is illegal under international law” and at the same time the US “did the right thing” by attacking. Slaughter, a foreign policy expert, adviser to Hillary Clinton, and frequent Trump critic, likens the situation to civil disobedience where law-breaking is justified — perhaps even demanded — by a higher principle.

The liberal view: we should respect international law, except when it stands in the way of loftier goals

The analogy to civil disobedience rests on the insight that the law, whether domestic or international, can lead to unjust outcomes and establish unjust structures of power. When it does, it may be more morally and politically justifiable to violate the law than to obey it. If the law on sovereignty — the principle that nations control what happens within their borders — and nonintervention protects President Bashar al-Assad’s capacity to kill civilians with chemical gas, then breaking that law to stop him may be excusable.

Paradoxically, Slaughter and other liberal internationalists see this kind of rule-breaking as a defense of the rules-based international order rather than its opposite. The international legal system remains the centerpiece of global affairs, in their eyes, and it coexists with the possibility (indeed, the necessity) of making exceptions when the law gets the wrong answer to a policy question.

This attitude toward international law might well be called Trumpian: It aligns well with Trump’s personal history of treating rules as things that apply only to other people. It counsels that when faced with a situation in which the rules forbid what you want to do, the path forward is to do it anyway and loudly proclaim that there are special circumstances that should allow you to do what the rules were clearly designed to prevent.

This looks like the principle by which Trump lives his personal and professional life, from taxes to contracts to emoluments to interpersonal relations.

And so it is with US military interventions — and not only under Trump. It may be illegal to use force against other countries, but when backed by the right motivations, military attacks sit in the exceptional space, a curious and productive gray zone in which they simultaneously flout and support the rules-based international order. Rules are made to be broken when you live simultaneously within and above the law.

The neoconservative view: international law is impotent parchment

Neither party lines nor views on international law cleave the pro-intervention coalition. It brings together Slaughter and John McCain with Trump and his maverick National Security Adviser John Bolton. The foreign policy establishment is now merged with the self-professed foreign policy radicals. To both camps, the fact that the attack violated international law seems to heighten its utility as a political message — if in slightly different ways.

It helps Bolton and Trump show that they are unconcerned about the constraints of international law, and it helps Slaughter and McCain demonstrate that higher principles may sometimes justify setting aside those constraints.

If illegality is excusable when important countervailing principles are at stake, who is to decide which principles and which stakes? In 1945, the UN Security Council was given this authority, and it has deployed it on rare occasions, notably in Kuwait in 1990. Today, the US government sees this as its own prerogative and claims for itself the power to decide on exceptions to the rules.

The lesson from the Syria episode is not that more faithful adherence is the way to go in foreign policy. Anne-Marie Slaughter is right that international law is a poor guide to appropriate foreign policy and rule-following is no guarantee of good choices or good outcomes.

Our attention can then turn away from debating the legality of military action and toward assessing the effects of military action. We should be asking what kind of world foreign policy produces, and whether it’s better or worse than the alternative — and on what scale and for whom? It is heartening to see an emerging, though odd, coalition in Washington that’s beginning to ask such questions.

If the unification of Trump with liberal internationalists comes as a surprise, then consider the pairing of Bernie Sanders and Charles Koch. The vision of foreign policy that Sanders laid out during the 2016 campaign has strong echoes in recent foreign policy activism by the Charles Koch Foundation. The views from these two sources converge on both the diagnosis of the problem and the prescription for a remedy.

Can you tell which of these statements comes from Sanders, and which from the Koch Foundation? One says that after “… years of ill-conceived and disastrous military engagements in the Middle East, it is time for a new approach. We must move away from policies that favor unilateral military action and preemptive war, and that make the United States the de facto policeman of the world.”

The other says, “America needs a sensible foreign policy. But in recent decades, our actions and decisions have failed to make us safer. Debates in Washington are often rooted in past conflicts and framed by insiders who demand ever-expanding military budgets and support few options beyond costly intervention.”

Strange bedfellows among the anti-intervention minority

Koch and Sanders hold antithetical intuitions about pretty much everything in domestic society, from inequality to taxes to corporate privilege. But they find common ground in the view that a militarized foreign policy has not served the US well. Military spending is the main driver of the federal deficit and crowds out domestic priorities, and both the socialist and the free market libertarian see scant evidence that American military intervention abroad has produced a better world for Americans or anyone else.

To be sure, Koch sees a less militarized foreign policy as one step toward a radical contraction of US government overall, in line with his desire that firms and private agencies take the place of state power. This is radically different from Sanders’s social democratic vision. But their shared skepticism of the payoff to military interventions — a mirror version of the Slaughter-Bolton coalition — is a useful reminder that the left-right spectrum is fairly useless for understanding foreign policy differences.

American foreign policy thinking sometimes looks like hawks as far as the eye can see. The myth that Democrats tend toward dovishness and Republicans toward hawkishness is not true; across Democrats and Republicans, liberals and neocons, it’s hawks all the way down.

To see beyond this mindset begins with an honest assessment of the effects of US militarism at home and abroad, in the economy and in society. When we do this, we are likely to find that the real problem with missile strikes in defense of international norms is not that they are illegal.

The real problem is that such strikes’ main accomplishments may be to produce the opposition to US policy that will then be used to justify the next round of missiles.

Ian Hurd is an associate professor of political science at Northwestern University. His most recent book is How to Do Things with International Law. Find him on Twitter @ian_hurd.

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