Was the Attack on Assad's Air Base Legal?

This article first appeared on the Just Security site.

I asked several of the very top legal minds about their views concerning Thursday night's airstrikes by the United States in response to the Syrian government's reported use of chemical weapons. I have provided their verbatim responses below.

Brian Egan

Former Legal Adviser, U.S. Department of State

It is essential that the United States articulate its international law justification for the strikes announced by the president Thursday night. As reported, the strikes do not appear to fit clearly within any of the widely recognized post-U.N. Charter international legal rationale for using force (self-defense, U.N. Security Council authorization, or host government consent).

Given the Assad regime's continued barbarity, the U.N. Security Council's repeated abject failure to act, and the apparently limited and tailored nature of the action taken by the United States, it is possible that the United States will attempt to justify these strikes by joining the United Kingdom in recognizing "humanitarian intervention" as a separate grounds for using military force under international law.

It is also possible—in light of the president's allusion to "threats to the United States and its allies"—that the administration will seek to justify these actions under a framework rooted in collective self-defense.

Regardless, U.S. government officials should quickly and affirmatively articulate what they view as the international legal framework for these actions—including whether and when further U.S. strikes would be justified.

A failure by the United States to articulate its international legal rationale could have consequences for continued cooperation with partners and allies, future military action by other actors in Syria and the region, and international crises in North Korea and elsewhere.

Philip Bobbitt

Herbert Wechsler Professor of Jurisprudence at Columbia, a Lecturer at the University of Texas, and a Former Senior Official in the U.S. government

In the abiding novel, Gilead, a departing grandfather leaves a note: It begins,

No good has come, no evil is ended.

That is your peace.

It could have been a note left by the departing U.S. president in 2017 about his policy in Syria. Now the U.S. has been compelled to redeem the promises of that administration in the face of new chemical attacks that violate the assurances given the U.S. in 2013.

In my judgment, we could scarcely do otherwise. The reasons we have hitherto not acted are obvious enough: we don't want to assist those Islamist elements, including but not limited to ISIS, that are fighting the Assad regime; we don't want to become embroiled in yet another Middle Eastern war; we hope for improving relations with Iran; and we don't seek an armed confrontation with Russia, to whom we have ceded a paramount external role in the conflict.

None of these reasons for not acting have much to do with international law. If anything, the emerging norms of humanitarian intervention support rather than negate American involvement.

President Donald Trump, the supreme realist in international affairs, has come up against the hollow core of Realism which would deny that the constitutional forms of a state have a great deal to do with its external behavior.

Moreover, Syria is not the first place in American diplomatic history that we have had to set priorities in the face of competing, and unattractive, but unavoidable options.

The note in Gilead goes on:

Without vision the people perish

We need a comprehensive strategy for the region, and indeed for our role in world affairs. Non-engagement is not sufficient. In fact it is not a strategy but rather a pose of nonchalance.

Related: What Trump's Syria strike means for Russia and Assad

Stephen Pomper

Former Special Assistant to the President and Senior Director for African Affairs, Multilateral Affairs and Human Rights, National Security Council

Thursday night's missile strikes have the potential to be enormously consequential, not just for Syria and the other countries to whom the U.S. government is trying to send a signal, but for the international order. Thus far, we have seen nothing by way of an international legal justification.

There was of course no U.N. Security Council mandate for the action and, as others have noted, the facts that have emerged so far do not seem to support a traditional self-defense justification that would permit force to be used consistent with Article 2(4) of the U.N. Charter.

While it may not be at the top of the administration's priority list to offer an international legal explanation for the strikes, what the U.S. government says and doesn't say about its legal justification in any Article 51 letter to the U.N. Security Council, and beyond, has implications for the sovereignty of every country in the world, and requires the most sober consideration.

The administration may be tempted to follow the script that the U.S. government adopted after the Kosovo intervention in 1999, where the U.S. intervention also lacked both Council authorization and a clear self-defense rationale. In that case, the State Department famously chose to deem the strikes "legitimate" without defending them as "legal."

That, however, was a tough line to walk with just one such intervention on the boards. With two, it becomes even harder. Both our partners and our adversaries are likely to get nervous about just how much space we are reserving for ourselves to act outside the bounds of the U.N. Charter.

Some may also have overlapping concerns about giving the Trump Administration too free a hand in deeming what is a "legitimate but not legal" use of force given campaign statements that suggested a perilous disregard for international norms.

Moreover, even if they don't have these concerns, we should be nervous about the implications of going down that path. Does the United States really want to convey to other international stakeholders is that there is an undefined, extra-legal gray zone where they can use force without regard to charter principles?

There is, of course, an alternative path, which would be for the U.S. government to craft an argument that Thursday evening's strikes were, in fact, consistent with the U.N. Charter.

Unfortunately, I do not have one in my hip pocket. Assuming no facts emerge to support a more traditional self-defense argument based on an armed attack or threat thereof against the United States, then it may be necessary to explore broadening our interpretation of when the right of self-defense is engaged.

Might the United States, for example, argue that the use of [weapons of mass destruction] in theaters where U.S. personnel are engaged engages the right of self-defense? Did the chemical weapons attacks arguably engage the self-defense rights of neighbors who might have invited the United States to act collectively with them?

Alternatively, U.S. government lawyers could consider whether to take the new and major step of arguing that the strikes are a form of humanitarian intervention permitted under the Charter. (In this connection, I agree with Harold Koh's call for international lawyers in and out of government to work together on possible approaches to humanitarian intervention that might gain the support of states.)

However the argument is framed, it will be important to tailor it narrowly to mitigate the risk that it will be deployed by an adversary for nefarious purposes.

U.S. government lawyers are likely deliberating now over the question of whether it is better to put forward an untested or novel legal rationale, or to run the Kosovo play once more. I hope they choose Door A.

There will invariably be risks in offering an untested argument, even if narrowly framed, but the risks of offering no argument seem greater. Not only would such an approach risk leaving an unbounded hole in Article 2(4) of the charter, but it would signal that the United States does not believe it needs to justify actions this consequential under international law.

That would be a dangerous signal to send about an increasingly fragile international order at an increasingly unpredictable time.

Related: Arab nations face stark choice: Israel or Iran

Michael Glennon

Professor of International Law at the Fletcher School of Law and Diplomacy, Tufts University; Legal Counsel to the Senate Foreign Relations Committee (1977-1980)

While it may be a good idea to punish Assad for using chemical weapons and to deter their use in the future, military action against Syria exposes the United States to the risk of retaliation and involvement in a wider war.

No national emergency requires that the decision to incur those risks be made by the president alone. The Constitution places that decision in the hands of Congress, not the president.

It's equally clear that the missile strikes against Syria violated the United Nations Charter, given that there's no plausible case to be made for self-defense or Security Council approval. The real question that's raised—yet again—is whether the charter restraints haven't been violated so many times by so many nations that they no longer constitute good law.

Jennifer Daskal

Associate Professor at American University Washington College of Law

The use of chemical weapons by the Bashar al-Assad regime is atrocious, a war crime, and fully deserving of a strong and decisive response—precisely of the type that the Trump administration delivered last evening, which reportedly targeted the air base from which Syria launched the attacks.

But no matter how just or right, there still needs to be a legal basis for the president's actions in both domestic and international law. This is essential for the long-term—to ensuring that uses of force are limited to situations of necessity and to ensuring democratic input and accountability for the extraordinary decision to engage in lethal force in another nation and potentially lead the United States into escalating war.

Others already have and no doubt will continue to have a lot to say about the international law justification. My focus here is on the domestic law issues. President Trump claimed that the strikes were in the "vital national security interest of the United States to prevent and deter the spread and use of deadly chemical weapons."

(Somewhat ironically, he also cited the refugee crisis that has emerged, perhaps forgetting that he has sought to bar for 120 days the admission of any refugees into this country—including the very victims of the Assad regime that he is now seeking to defend.)

In so claiming, he appears to be laying out his purported justification for the use of force—suggesting that the strikes are justified pursuant to the president's Article II authorities. The threat he is responding to: the potential spread and use of chemical weapons and the refugee crisis that has emerged from the brutality of the Assad regime.

But the risks posed by chemical weapons and increased number of asylum seekers—while horrific—aren't the kind of imminent existential threat that requires immediate executive action.

Nor does is fall within the kind of historically supported national interests that have previously been relied on to support the uses of unilateral and limited uses of force. (See Marty's discussion here). Rather, it is precisely the kind of thing that deserves congressional consultation and consent.

The Founding Fathers, after all, gave Congress the declare war authority and the executive the make war authority for a reason. They wanted to ensure that the weighty decisions to use military force were subject to broader debate and discussion—as well as input from the American people. In sum, the president seems to be stretching his claimed Article II authority beyond what can be legitimately defended and cutting out Congress in the process.

Some may applaud this as a means of ensuring decisive and swift action in the wake of something as heinous as a leader gassing his own people. And I am partially persuaded. But the merits of the president's actions might not always be so clear.

Next time it may be less evident that this is the right thing to do. And once the strikes are launched, it's too late to take them back. The conflict almost inevitably escalates, even if it may ultimately be tamped down.

That said, it is not too late. President Trump can still go to Congress. And he should. He should spell out the goals, objectives, and end game. And should Congress agree, it should grant him the authorization to respond to this and any other future use of chemical weapons or indiscriminate attacks on civilians, while also setting the contours of any permissible and ongoing response.

Fionnuala Ni Aolain

Robina Chair in Law, Public Policy, and Society at the University of Minnesota Law School and Professor of Law at the University of Ulster's Transitional Justice Institute in Belfast, Northern Ireland

The use of force in Syria underscores the ongoing erosion of U.N. Charter norms on the lawful use of force under international law. Hard cases make bad law, and outrage about the cynical use of chemical weapons by the Assad regime should not delude us that the means (force) justify the ends (presumably a warning shot not to use these weapons again against civilians).

While there is precedent for the use of force without Security Council authorization, including by the United States in Kosovo, these actions, Kosovo included weaken the Security Council and the post War War II global system of collective security.

Despite the flaws of that legal order, a slide into self-justificatory unilateralism by the United States should not be celebrated nor validated. Legalities aside, and acknowledging that there are fundamental questions as to the legality of this attack, a broader set of global institutional and collective processes are undermined by U.S. action.

These effects should worry us as much as the legality of the use of force itself.

Derek Jinks

The Marrs McLean Professor in Law, University of Texas School of Law

There is no clear legal basis for the strikes against Syria in international law. Indeed, the strikes seem to constitute a clear violation of the U.N. Charter. The charter prohibits the "use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations."

The two clearly established exceptions to this fundamental rule are seemingly inapplicable. The Security Council has not authorized the use of force against Syria. And although the Trump administration has not offered a formal legal justification for the strikes, it does not appear that the U.S. could invoke a plausible self-defense claim.

There may good reasons to think that a third exception for humanitarian intervention is emerging in international law—either as a matter of custom or as a matter of charter construction. In my view, state practice regarding the legality of humanitarian intervention at present is neither sufficiently extensive nor sufficiently uniform to support the conclusion that the charter permits it.

The strikes might constitute an important precedent—and perhaps a watershed moment—driving the emergence of a new rule permitting humanitarian intervention in some circumstances.

Instances of illegality in international law—particularly when widely perceived as justified and legitimate—might serve as a catalyst for a change in the law even without a revision of the relevant treaties. For these strikes to promote such a change, at least two things would need to happen.

First, the Trump administration would need to provide a fully articulated defense of the strikes on humanitarian grounds—and explain when such uses of force are justifiable.

And second, some non-trivial fraction of the international community would need to react to the strikes in such way as to make clear its endorsement or acceptance of this defense.

Michael Ramsey

Hugh and Hazel Darling Foundation Professor of Law Director, International & Comparative Law Programs, University of San Diego School of Law

President Trump's military action against the Syrian government is unconstitutional under the Constitution's original meaning. The framers understood the declare war clause to require Congress to approve attacks on foreign nations.

That the goals of the strike are laudable, that quick action may have been needed, or that vital national security interests are said to be at stake does not change the Constitution's basic rule. The framers did not want the president to have unilateral power to involve the U.S. in military conflict.

President Trump may argue (as President Obama did with his 2011 Libya intervention) that the action is too small to count as "war" for constitutional purposes and so approval is not required. But that is not how the framers saw it. In the immediate post-ratification era, even low-level uses of force—such as the 1798 "Quasi-War" with France and the 1801 naval action against Libya—were widely thought to require congressional approval.

President Trump's actions are regrettable from a modern constitutional perspective. President Obama declined to use force against the Syrian government without congressional approval.

He was criticized for this hesitation, but it was the right call, constitutionally speaking. It established a precedent (somewhat balancing Obama's own unilateral action in Libya) in keeping with constitutional limits.

Unfortunately that precedent is undermined by the current action, which reinforces the modern (and unconstitutional) idea of presidential unilateralism.

Louis Fisher

Scholar in Residence, the Constitution Project

President Trump has no constitutional authority to unilaterally commit the nation to war against Syria, which is the effect of launching cruise missiles against Syria.

From 1789 to 1950, presidents came to Congress either for a declaration of war or statutory authority whenever they decided it was necessary to take the country from a state of peace to a state of war. In doing so, they complied with the framers' clear intent that the decision to use offensive force against another country must reside solely in Congress.

However, from Truman's war against North Korea in 1950 to Obama's use of military force against Libya in 2011, presidents have ignored that fundamental constitutional principle.

Instead of seeking authority from Congress, presidents turn instead to the U.N. Security Council or NATO allies for support. The result: a series of unconstitutional wars.

Saikrishna Prakash

James Monroe Distinguished Professor of Law and Miller Center Senior Fellow, University of Virginia

Yesterday, the president declared war against Syria. Or at least he did if we understand the Constitution as the founders did. By granting Congress the power to "declare war," the founders granted Congress a monopoly on whether the nation ought to wage war, a decision grounded on the claim that a more complicated, deliberative process ought to be used to make such dreadful decisions.

The president might be involved in that he might suggest a war or veto a proposed declaration. But the founders never authorized him to wage war on his own say so.

President Trump chose a different path, one well trodden over the past half century. A number of modern presidents have declared that they may use military force (sometimes euphemistically called "kinetic" action) without any prior congressional authorization.

Some scholars support the basic claim, asserting that practice has put a "gloss" on executive power, in a Frankfurterian way. Some scholars suppose the president can start small wars but can't start big ones. Other scholars say that practice establishes that the president can start any war he pleases, with the only checks arising from public opinion and Congress.

Whether legal as a matter of domestic law, the airstrikes are bound to mystify many. Trump's allies who sought fewer wars are apoplectic that Trump may have begun another forever war.

Those of Trump's critics who imagined he was a puppet of Vladimir Putin now have to decide whether to contemplate a new conspiracy, one in which Putin wanted Trump to attack Putin's most stalwart Middle East ally.

Ryan Goodman is co-editor-in-chief of Just Security and the Anne and Joel Ehrenkranz professor of law at New York University School of Law. He served as special counsel to the general counsel of the Department of Defense (2015-2016).