Thank you to Harold Koh for spurring (here and here) a discussion about some of the most important issues of our time—on matters concerning wars of choice and building an effective response to atrocity, and on the role of lawyers and the place for political judgment. I thought to add three notes to the debate that occupied the pages of Just Security (David Kaye & Maj. Kurt Sanger), opiniojuris (Kevin Jon Heller & Carsten Stahn), Air Force General Counsel Blog, EJIL Talk!, and Twitter.

1. Prohibition on the threat to use force

Non-legal specialists should not overlook a subtle point in the debate: the UN Charter forbids not only the unlawful use of force—it forbids the unlawful “threat or use” of force. Accordingly, the claim that humanitarian intervention in Syria would violate the Charter, does not simply implicate possible future scenarios. If that claim is correct, President Obama is currently acting in flagrant disregard of the Charter by threatening the Assad regime with a military response to the use of chemical weapons. And, if the President has ordered the military to plan or prepare for an attack in manifest violation of the UN Charter he is presumably guilty of the war crime of aggression.

So, why have Koh’s detractors not taken these positions and followed their textualist argument to its logical endpoint? And why does Koh’s response make such great use of the fact that the President’s threat to use force is widely considered beneficial? Indeed, he almost dares the critics to oppose the threat of force against Assad.

The answer may be because part of what Koh wishes for (in the law on the use of force) is already a reality. The threat to use force for humanitarian intervention essentially gets a legal pass.

This of course would not be the first evolution in thinking about the meaning of the UN Charter. Its text has been subject, like many instruments of law, to new interpretations over time—interpretations that become conventional contemporary understandings and that the original framers would have considered unfathomable. If we were stuck with the version of the original framers, for example, “abstention” votes by P-5 members in the Security Council would be considered vetoes (hence, no referral of Darfur to the International Criminal Court).

The threat to use force for humanitarian purposes may be another example of change in meaning over time. Today, if a Head of State threatened to use force to collect a debt from another nation, her threat alone would be met with international outrage. Yet, as political scientist Martha Finnemore explains, it was not too long ago that the invasion of another country to enforce debt collection was considered a legal, legitimate, and rightful act. Finnemore also tells us that the multilateral use of force for humanitarian ends is now perceived as legitimate within the international legal order far more than only a few decades ago. Indeed, the threat to use force for humanitarian reasons would have been anathema to the drafters of the UN Charter.

Lastly, a revealing irony in the debate with Koh is that his detractors rely on the idea that the Security Council is the legally appropriate institution to authorize force in Syria. Yet, if we stuck to the text and understanding of the original framers, the Security Council would have no such power.

It is important to understand changes in both of these practices–Security Council authorization to use force to stop atrocities and unilateral threats in such cases. Indeed, these are certainly not the only areas of international law in which doctrines that protected state sovereignty eroded over time under the weight of contemporary human rights norms (see notes 40 & 50 of this article on foreign official immunity).

2. Illegal but not unprecedented

If the United States does use force in Syria without a Security Council go-ahead, its actions will be illegal—but not unprecedented. There are several more cases than Kosovo. In the earlier phase of the UN Charter, Tanzania invaded Uganda to oust Idi Amin, India launched an invasion in response to massacres of civilians in East Pakistan, Vietnam invaded Cambodia to oust the Khmer Rouge, and India flew military jets into Sri Lanka to escort cargo planes dropping supplies to Tamil civilians under attack from the Sri Lankan forces. These were, of course, also mixed-motives interventions, but the humanitarian element reduced the international opposition to them.

After the Cold War, such interventions without Security Council authorization were conducted by multilateral coalitions. The US, France, and the UK conducted years of safe havens inside and No Fly Zones over Iraq initially to protect the Kurds and later to protect the Shiite population as well. Other states assisted by providing for bases and flight paths. The US, France, and the UK invoked Security Council Resolution 688 to support their actions—but any close observer knew that was a legal hoax. Indeed, the Resolution was purposefully not issued under Chapter VII of the UN Charter, because Russia and China promised to veto any such reference. In a leading book on the contemporary history of humanitarian intervention, Nicholas Wheeler explained (in a lesson that the White House today could have benefited from):

How, then are we to account for the fact that no Security Council member who voted for this resolution publicly challenged the West’s legal right to create the safe havens?… “Chinese and others … were willing to tolerate actions de facto that they would not authorize de jure.” (quoting Jane Stromseth)…

[N]one of these states wanted to be exposed publicly as opposing a rescue mission that was saving lives and they were shamed into silence. Acquiescence, then, rather than tacit legitimation captures the response of those governments to Western intervention.

In the early 1990s, the Economic Community of West African States invaded Liberia without prior Security Council authorization. And, the coalition later invaded Sierra Leone without getting approval beforehand. Most recently, NATO’s actions to oust Qaddafi arguably exceeded the authority granted to it by the Security Council.

3. The limbo world — of illegal but not unprecedented — may be optimal

The existing state of affairs—illegal but not unprecedented—may be the best outcome for international law and humanitarian values.

Koh argues for a legal system that expressly permits the use of force without Security Council approval to stop an atrocity—a system he explains is like “the criminal law [which] has crafted rules that exempt ambulance drivers who run red lights in extremis.” For the international order, however, a better rule may be one that formally prohibits anyone running the red light but leaves ambiguity about exceptions for rescuers. In that system, actors have to engage in greater efforts to justify and prove the genuine nature of their behavior. And, it is actually good to give powerful states reason to pause before launching a war. At the least, this line of analysis should be a part of the debate, and for an original expression and elaboration of this idea, I recommend an essay by Jane Stromseth in which she explains:

This essay argues that the legal status of humanitarian intervention without Security Council authorization remains uncertain after Kosovo and that this, in fact, is a good thing. The uncertain legality of humanitarian intervention puts a very high burden of justification on those who would intervene without UN authorization. Yet this very ambiguity is also fertile ground for the gradual emergence of normative consensus, over time, based on practice and case-by-case decision-making. … The most promising path for the future does not involve a formal doctrinal framework that attempts in advance to reconcile human rights principles and the Charter’s non-intervention norms. Instead, it lies in identifying patterns and common elements in recent practice as guidance for the future ….

Ultimately the Stromseth approach may be consistent with David Kaye’s argument (see his final para.) that political leaders should be told that the UN Charter forbids unilateral humanitarian intervention and thus act when they are willing to pay the price of illegality. That said, Stromseth’s approach does not work unless Koh’s analysis of the direction of the legal norms is mostly correct.