There has been much commentary about the fact that the new (and as yet unnumbered) U.N. Security Council Resolution on Syria is not explicitly a “Chapter VII” resolution. (Chapter VII of the UN Charter specifies actions the Security Council may take in response to threats to international peace and security. Resolutions adopted under Chapter VII are generally viewed as legally binding on the affected parties.) So, what is the meaning of this, and is the new resolution legally binding under international law? From a U.S. perspective, notwithstanding the absence of an explicit present-tense reference to Chapter VII, certain operative paragraphs of the resolution are clearly legally binding and (as Jack noted yesterday) require the Security Council to impose some unspecified measures under Chapter VII in the future in the event of non-compliance. Whether these future measures under Chapter VII would include an authorization to use force to compel compliance seems unlikely, however.

There is no agreed form of words to make UNSCRs legally binding and, over the last sixty years, the Security Council has been inconsistent in its practice. In recent years, many international law experts (including many government lawyers for the P-5 members of the Security Council) have agreed that, to ensure absolute clarity that a resolution is legally binding, the resolution should contain three elements:

A determination or finding that there is a “threat to international peace and security”

A statement, usually in the last preambular paragraph, that the Council is “Acting under Chapter VII” of the UN Charter

Use of the verb “Decides” in any operative paragraphs intended to be binding.

But these three elements are not absolutely necessary, and not all recent resolutions intended (at least by the United States) to be legally binding have contained all three elements. For example, UNSCR 1973 (2011), which authorized the no-fly zones over Libya, contained all three elements, as did UNSCR 1441 (2002), which imposed the weapons inspection regime on Iraq. On the other hand, UNSCR 1695 (2006), which demanded that North Korea suspend its missile program, did not specifically mention Chapter VII or make a determination that there had been a threat to peace and security.

In general, the absence of one of the “best practice” elements means that one or more of the P-5 members has resisted inclusion of an element in order to retain constructive ambiguity regarding the effect of the resolution. After the use of force by the U.S. in Iraq and Libya, both Russia and China have been particularly reluctant to include any reference to Chapter VII in order to avoid giving the U.S. any cover at all to use force.

The Syria resolution contains two of the three “best practice “ elements. It contains not one but two determinations that the use of chemical weapons constitutes a threat to international peace and security (PP13 makes the determination with respect to their use inside Syria and OP1 makes the legally significant determination that their use anywhere constitutes such a threat). The Security Council also specifically “decides” in operative paragraphs that the Syrian government and any party in Syria shall not produce, use, acquire or store chemical weapons; that Syria shall comply with UN weapons inspectors; that the Security Council will review Syria’s compliance; and that the Council will impose “measures under Chapter VII” in the event of non-compliance. However, rather than including a specific statement that the Council is “Acting under Chapter VII,” the resolution states that the Council is “Underscoring that Member States are obligated under Article 25 of the Charter of the United Nations to accept and carry out the Council’s decisions.”

The reference to Article 25 (instead of Chapter VI or VII) is very unusual, but does not vitiate the legally binding nature of the resolution. Even without the reference to Article 25, the inclusion of the other elements would be sufficient to make the operative “decides” paragraphs legally binding. The Article 25 reference in fact emphasizes that these “decisions” are binding, but without including references to Chapter VII which were likely resisted by Russia and China.

In short, the Syria resolution is a strong, legally binding resolution that reflects the political compromises that typically take place in the Security Council. For the time being, the Obama Administration can be justifiably proud of it. The problem, of course, is that it simply kicks the can down the road. If Syria does not comply fully with its obligations (and I would be surprised if Syria does so), this will bring the whole matter back to the Security Council within a few months. At that point, Russia and China may (or may not) be willing to make good on their commitment to take action under Chapter VII (such as by imposing sanctions), but they are highly unlikely to authorize the use of force that President Obama has threatened. And then, President Obama, like President Bush after Iraqi non-compliance with UNSCR 1441, will be faced with a difficult decision how to respond.