Jared Zimmerman is an M.A. candidate at American University’s School of International Service where he is studying United States Foreign Policy and National Security with a concentration in terrorism and political violence.  He can be found on Twitter @jaredezimmerman.  Divergent Options’ content does not contain information of an official nature nor does the content represent the official position of any government, any organization, or any group.

Title:  Assessing How Article 51 of the United Nations Charter Prevents Conflict Escalation

Date Originally Written:  March 8, 2018

Date Originally Published:  June 4, 2018.

Summary:  Article 51 of the United Nations Charter is sufficiently vague to allow states to assert their right to self-defense without escalating a conflict. While either side in a conflict may see the other as the aggressor acting beyond mere self-defense, Article 51 is vague enough that neither side can prove the other has acted offensively. This vagueness can aid in, if not the de-escalation of conflicts, preventing the rapid escalation of conflicts.

Text:  The first sentence of Article 51 of Chapter 7 of the United Nations Charter reads as follows:

Nothing in the present Charter shall impair the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations, until the Security Council has taken measures necessary to maintain international peace and security[1].

This sentence is particularly vague on the following points:

  1. It does not define what constitutes an attack. Is the seizure of ships or aircraft an attack? Is the accidental or intentional violation of another country’s airspace an attack? Is industrial espionage an attack? Is a spy satellite taking photographs of military installations an attack?
  2. It does not define what constitutes an armed attack. For example, is a cyber attack an armed attack?
  3. It does not define “collective self-defence.” Does the attacked nation need to request assistance or can other nations preemptively intervene and claim their intervention constitutes collective self-defense? Requiring the attacked nation to request assistance might seem like the most responsible position, but this requires that the United Nations Security Council determine who the original aggressor and defender are. This determination may not be possible or delivered in a timely manner.
  4. The phrase “…until the Security Council has taken measures necessary to maintain international peace and security” begs several questions. What if the Security Council does nothing? What if the Security Council does act, but these actions are not sufficient to resolve the conflict? What constitutes a resolution and who decides whether a resolution is satisfactory?
  5. The phrase: “international peace and security” also begs several questions. What is international peace and security? Was the world at peace during the Cold War? Is the world not at peace when great powers are not in conflict but relatively small regional or civil wars are ongoing? Is the world at peace when there is no open conflict between states but despots murder and oppress their own people?

It is apparent from the questions in the preceding paragraphs that the first sentence of Article 51 is exceedingly vague. Opposed parties in a real-world conflict are certain to interpret portions of the sentence in their own best interest, and these interpretations could be wildly different yet equally valid[2]. But this begs the question, does this vagueness expand and escalate conflicts or limit and de-escalate them?

On the surface it might appear that a more explicit Article 51 is to be desired. If it was clear to states what actions constitute an armed attack and what circumstances allow for collective self-defense, perhaps states would judiciously aim to abide by these rules lest they risk United Nations’ intervention. There are several problems with this approach:

  1. It would be impossible to explicitly account for all types of armed attacks, not simply because of the variety that exists today, but because new types are continually being invented. For example, the authors of the United Nations Charter could hardly have conceived of cyber warfare in 1945.
  2. States are ingenious and will always find new ways to circumvent—or even outright ignore—any explicit rules that are laid out.
  3. If a state realizes it must break one explicit rule to advance its agenda, why not break more? If the United Nations Security Council does not intervene when one rule is broken, will it if two are broken? Three? Four? States will test how far they can push the boundaries because it is advantageous to do so.

Is it possible, however, that having a vague Article 51 is advantageous? The world is not rigid, so would it be beneficial to have a rigid Article 51? Given the reasons above, a rigid Article 51 is certainly not practical. Let us take the Iranian drone shot down by the Israeli Defense Force in February 2018 as an example of the advantages of a vague Article 51.

On February 10th, 2018 an Iranian drone entered Israeli airspace and was shot down by an Israeli helicopter. The Israeli Defense Force followed up by attacking what they believed to be the “drone launch components in Syrian territory[3].” Later, Israeli Air Force (IAF) aircraft attacked 12 targets in Syria, including a mix of Syrian and Iranian military targets. “During the attack, multiple anti-aircraft missiles were fired at IAF aircraft. The two pilots of an F-16 jet ejected from the aircraft as per procedure, one of whom was seriously injured and taken to the hospital for medical treatment[4].”

To summarize, Iranians in Syria used a drone to violate Israeli airspace. The Israelis responded by destroying the drone and the drone’s launch structures in Syria. The Israelis then violated Syrian airspace to attack Syrian and Iranian infrastructure. While doing so, one of their F-16’s was shot down and one of its crew was wounded. All of this has occurred, yet Iran and Israel have not declared war in response.

Incidents like this are so common that it is easy to overlook the miraculous fact that while such incidents are not “peaceful,” the world does not face open war in response to each of them. There are certainly a variety of reasons for this lack of open war that can be unique to each situation such as level-headed leaders on either side, mutually assured destruction, war-weary populations, etc. One compelling reason that many share, however, is that each side can claim it was acting in self-defense while not being able to convince the international community and United Nations Security Council that this is true. In this above example, Israel could claim that it was attacked when the Iranian drone entered its airspace so its response was in self-defense. Iran and Syria could claim that their drone was unarmed and entered Israeli airspace accidentally. Israel then attacked them and they downed an Israeli aircraft in self-defense. This familiar dance occurs in other comparable situations: opposing sides take limited aggressive actions towards each other but generally stop short of open war. Article 51 doesn’t eliminate conflict, but prevents it from escalating or at least escalating quickly.


[1] United Nations. (n.d.). Charter of the United Nations: Chapter VII. Retrieved February 27, 2018, from http://www.un.org/en/sections/un-charter/chapter-vii/

[2] Glennon, M. (2018, February 13). ILO L201: Public International Law [Class discussion]. The Fletcher School of Law and Diplomacy at Tufts University, Medford, Massachusetts, U.S.

[3] IDF intercepts Iranian UAV. (2018, February 10). Retrieved February 28, 2018, from https://www.idf.il/en/minisites/press-releases/idf-intercepts-iranian-uav/

[4] IDF intercepts Iranian UAV. (2018, February 10). Retrieved February 28, 2018, from https://www.idf.il/en/minisites/press-releases/idf-intercepts-iranian-uav/