Editor’s note: this webpage is the text of a portion of “Quantum of Silence: Inaction and Jus ad Bellum,” by Dustin A. Lewis, Naz K. Modirzadeh, and Gabriella Blum, HLS PILAC, 2019. A link to the PDF version of this part is available here, and a link to the full paper and annex is available here.
HLS PILAC Catalogue of Communications to the Security Council of Measures Taken by United Nations Member States in Purported Exercise of the Right of Self-Defense: October 24, 1945 through December 31, 2018
Editor: Dustin A. Lewis
Contributors: Lindsay Anne Bailey, Emma Broches, Laura Clark, Sonia Chakrabarty, Thejasa Jayachandran, Daniel Levine-Spound, Sarah Libowsky, Samantha Lint, Yang Liu, Carolina Silva-Portero, Shira Shamir, William Ossoff, Tamsin Parzen, and Shanelle Van
So far as we are aware, no existing resource provides a searchable, up-to-date, free-of-charge catalogue of communications to the United Nations Security Council of measures taken by U.N. Member States in purported exercise of the right of self-defense since the adoption of the U.N. Charter in 1945. To help fill this apparent gap, a team of researchers at the Harvard Law School Program on International Law and Armed Conflict (HLS PILAC) set out in 2018 to create a catalogue of so-called “article 51 communications” and certain responses by the Security Council to those communications.
In the authentic English text, article 51 of the U.N. Charter provides 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. Measures taken by Members in the exercise of this right of self-defence shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary in order to maintain or restore international peace and security.
The first part of the second sentence of article 51 expressly establishes the obligation of each U.N. Member State to bring to the attention of the Security Council measures taken in (purported) exercise of the right of self-defense. Submission of such an “article 51 communication” thus satisfies a Member State’s obligation under the first part of the second sentence of article 51. The U.N. Charter contains no (further) express provisions regarding the format or content of those communications. It has been argued that the drafting record of what became the reporting obligation laid down in article 51 reveals that the obligation initially arose as part of an attempt to centralize the use of force in the U.N. system and to give the Security Council the opportunity to scrutinize claims of self-defense. When submitted in the form of a document, or perhaps in a set of documents, such reports are sometimes informally labeled “article 51 letters,” “article 51 reports,” or “article 51 communications.”
In addition to seeking to fulfill an obligation laid down in the U.N. Charter, “article 51 communications” may be legally relevant for other reasons. For example, “article 51 communications” might reveal submitting States’ views regarding at least certain aspects of the international legal framework concerning self-defense. For example, an “article 51 communication” may — expressly or implicitly (or both) — convey the submitting State’s interpretation regarding legal elements of self-defense, including in relation to such issues as the authorship, form, and scale and effects of what may constitute an “armed attack”; in respect of what contexts self-defense may be undertaken, for what duration, and against whom; and the scope of the jus ad bellum necessity and proportionality principles. An “article 51 communication” may, under certain circumstances, itself constitute State practice or evidence of acceptance as law (opinio juris), or perhaps both, of the submitting State — that is, one or the other, or perhaps both, of the two elements generally recognized as necessary to identify rules of customary international law. In turn, responses to “article 51 communications,” which sometimes themselves might take the form of an “article 51 communication,” may reveal other States’ views concerning legal aspects of self-defense. Meanwhile, at least in accordance with the view of the ICJ, an absence of an “article 51 communication” may, under certain circumstances, be construed as having legal significance.
A. Target Audience
The primary intended audience of the catalogue includes legal practitioners and scholars whose work concerns self-defense in particular and the legal regime governing the non-use of force in international relations more generally.
B. Identifying Communications; Caveats and Limitations
To identify candidate communications, the research team primarily utilized the U.N. Official Documents System (ODS). Researchers started by conducting an initial search by entering the following search parameters in ODS:
Symbol field: “S/”
Full text search: “self-defense”; “self-defence”; or “Article 51”
Type of full text search: Find any of these wordsThrough that process, some “false positives” were identified — for example, S/2016/869 (United States), in which the United States expressly indicates that it does not believe that notification pursuant to article 51 is necessary in the particular circumstances. Those “false positives” were not ultimately included in the catalogue.
For each returned result, a researcher conducted an initial evaluation as to whether the communication met the parameters for inclusion, which are described below. The candidate communications that passed provisional muster were then reviewed by the general editor of the catalogue. The general editor alone ultimately decided whether or not to include each candidate communication in the catalogue.
As a preliminary matter, it bears emphasis that it is not clear that all of the communications recorded in the catalogue necessarily contain authentic claims of a purported exercise of the right of self-defense as contemplated in the second sentence of article 51 of the U.N. Charter. Nor is the catalogue necessarily comprehensive. So far as the general editor is aware, there is no authoritative, authentic, and comprehensive catalogue either of article 51 communications or of Security Council responses (or lack of responses) thereto. Therefore, several editorial and interpretive decisions were made — including in respect of what communications to include and which to exclude — that may be subject to critique. Moreover, several technical difficulties were encountered in searching for candidate communications.
Searches in the U.N. Official Documents System did not necessarily produce a comprehensive set of “article 51 communications.” This might be due in part to limitations concerning the technical searchability of PDFs created by scanning paper documents. Those limitations arise in part because the digital surrogates — that is, the PDFs in the U.N. Official Documents System — of the original paper documents are of varying quality. To help address this issue, for letters at least from the 1945–1986 period, researchers also conducted searches within the United Nations Dag Hammarskjold Library, which is an additional U.N. online document catalogue. For those searches, researchers entered the following search parameters in the DAG Repository of U.N. Official Documents:
Content type: Letters/Notes Verbales
Search: “self-defense”; or “self-defence”In seeking to ensure that every relevant report was evaluated, researchers also reviewed other resources, including existing catalogues and research tools that contain apparent “article 51 communications.”
Several other difficulties arose in seeking to identify and systematically evaluate candidate communications.
As an editorial matter, in deciding which candidate communications to include, the general editor ultimately elected to read the requirements laid down in article 51 relatively strictly. Therefore, researchers were instructed — in evaluating whether or not to include a communication — to confirm or disconfirm whether a candidate report could be reasonably construed, in the terms of the second sentence of article 51, as immediately reporting to the Security Council “[m]easures taken by [a U.N.] Member in the exercise of this right of self-defence [that is, the inherent right of individual or collective self-defence if an armed attack occurs against a Member of the United Nations].” On that basis, only those communications that were reasonably construed as meeting six sets of criteria were included: those communications that (i) reported, whether in writing or verbally, (ii) immediately (iii) to the Security Council (iv) measures taken (v) by a U.N. Member State (vi) in (purported) exercise of the right of self-defense.
Regarding element (i), it is not necessarily clear whether only written communications may count or whether verbal statements may (also) satisfy the reporting requirement. So far as the general editor of the catalogue is aware, the Security Council has never directly and authoritatively addressed that specific question as such, nor have other U.N. Organs or U.N. Member States writ large. The catalogue presumes that both written and verbal communications may count and therefore includes both types of communications.
Further with respect to element (i), it is also not necessarily clear whether, to satisfy the reporting requirement, the communication must, among other things, expressly invoke “self-defense” (or “self-defence”); expressly invoke “article 51”; and/or expressly indicate the existence — and perhaps the author (or authors) — of an “armed attack.” So far as the general editor of the catalogue is aware, the Security Council has never directly and authoritatively addressed that question in relation to the reporting requirement, nor have other U.N. Organs or U.N. Member States writ large. The catalogue of reports includes communications even if they lack those express invocations, provided that the communication may (otherwise), at least on a prima facie basis, be reasonably interpreted to constitute a report of measures taken in a purported exercise of the right of self-defense.
Communications that invoked “article 51” but that did not (otherwise) satisfy the six constituent elements were not included in the catalogue.
Conversely, a lack of an express reference to “article 51” did not by itself constitute a ground to exclude the communication from the catalogue. That interpretive decision was made on the basis that the text of article 51 does not expressly require that, in calling relevant measures to the attention of the Security Council, a U.N. Member must necessarily expressly refer to “article 51.”
Regarding element (iii), communications made to other U.N. entities but not (also) to the Security Council were excluded. Where a document was circulated to both the Security Council and the General Assembly, only the Security Council symbol was recorded in the catalogue.
In relation to element (iv), the catalogue might be considered under-inclusive to the extent that it includes only communications of measures that have already been taken; thus, the catalogue does not include what Professor James Green has characterized as “pre-emptive” reporting. In addition, communications that entail threats by a State (or States) to use force in self-defense or signal that the State(s) would in principle be entitled to use force in self-defense, but that are not accompanied by an actual defensive response, were not included. The choice on the part of the catalogue’s general editor to exclude such communications might be critiqued on the basis that excluding those reports could distort the broader legal picture by, for example, perhaps downplaying the practice of militarily weaker States that may not be in a position to respond by force to an alleged armed attack. The choice not to include certain other communications — namely, those that expressly or implicitly indicated that measures would be taken if certain conditions were met in the future, or that (merely) “reaffirmed” or “reserved” the right of self-defense, but that did not report that any (new) measures had already been taken — also reflects an editorial decision.
With respect to element (v), an editorial decision was made to include only communications containing reports of relevant measures taken by the reporting State. Thus, reports of measures taken by other entities were excluded.
With respect to element (vi), only those measures considered by the general editor to fall within the concept of the right of self-defense in the face of an armed attack as “enshrined” — in the words of the ICJ in the Military and Paramilitary Activities in and against Nicaragua case — in the first sentence of article 51 of the U.N. Charter were included. It bears emphasis, however, there is a lack of universal agreement as to the precise contours of what measures may fit within that concept. It was therefore necessary to take several editorial decisions in this connection — for example, whether or not to include “defensive” military action following an alleged breach of an armistice line. (Ultimately, the decision was made by the general editor to include such actions.) Conversely, measures of “defense” of U.N. peacekeeping or peace-enforcement missions were not included, on the basis that they are apparently not (usually) taken in relation to article 51.
Spanning out, these and other editorial and interpretive issues that the research team encountered might be seen as underscoring the relative lack of authoritative, authentic, and comprehensive legal guidance in this area.
Despite these limitations and caveats, it is hoped that the catalogue will provide a useful — if limited — basis to identify and evaluate the context and development of the positions of States and the Security Council over time in relation to self-defense.
IV. Parameters of the Catalogue
A. Versions and Formats
Version 1.0 of the catalogue is being released on the HLS PILAC website (https://pilac.law.harvard.edu) in July of 2019. If changes are made to the catalogue, subsequent versions will be updated as different versions. The catalogue is being released in July of 2019 in the following formats:
- As an Excel Spreadsheet;
- As a PDF; and
- As a Google Sheet.
The content of the catalogue is the same across formats.
B. Catalogue Fields
The catalogue includes the following fields:
This column records the chronological order of the communication, in descending order (that is, from oldest to newest).
Date of Comm.
Date of communication — for written reports, this is the date of the document in which the communications was sent to the Security Council; for verbal reports, it is the date of the statement that brought the report to the attention of the Security Council. For written reports, this date is usually found in the subject line of the document transmitting the report. The date is in the following format: Year.Month.Date [YYYY.MM.DD].
Date of UNSC Document
This column records the date on which the communication was published in a Security Council document. This date is sometimes (slightly) after the date the communication was conveyed by the submitting Member State. The date is in the following format: Year.Month.Date [YYYY.MM.DD].
This column records the Security Council symbol pertaining to the communication: where both a General Assembly and a Security Council symbol are included on the document, only the Security Council symbol is recorded in the catalogue. For example, S/2005/609 (Israel) is recorded, whereas A/60/382-S/2005/609 (Israel) is not recorded. Corrigenda were not recorded in the catalogue; for example, S/9330 (El Salvador) is recorded, but S/9330/CORR.1 (El Salvador) is not (also) recorded.
Member State(s) That Submitted the Comm.
This column records the U.N. Member State that submitted the communication to the Security Council. For ease of reference and consistency in reporting, certain spellings were standardized or shortened in the database.
Expressly Mentioned UN Members (& Colonial Holdings & Protectorates, if any)
This column records all States, colonial holdings, and/or protectorates explicitly mentioned in the communication, in any respect, including the Member State submitting the communication.
Express or Implied Assertion of Individual, Collective, or Both Self-defense
This column indicates whether — in the view of the general editor — the measures taken in purported exercise of self-defense were expressly or impliedly undertaken in individual self-defense, collective-self-defense, or both individual and collective self-defense. If neither “individual” nor “collective” is stated verbatim in the communication, the measures contained in the communication were labeled as constituting (as applicable) an implied assertion of “individual” or “collective” self-defense or both “individual” and “collective” self-defense. Only those communications that contain an express invocation of “individual” self-defense, “collective” self-defense, or both “individual” and “collective” are recorded as an express assertion of self-defense in this column.
Nature of the Alleged Threat
This column indicates whether — in the view of the general editor — the nature of the threat that is addressed in the communication might be characterized as one or more of the following: a conducted attack; a threat of attack; an imminent attack; and/or an indirect attack. As a matter of emphasis, it is noted that these categories are rough sketches and do not correspond to legal categories as such. The categories included in this column are not meant to correspond to such legal notions as “armed attack,” “threat of force,” or the like.
Expressly Alleged Author(s) of the Threat (If Any Indicated)
This column records the alleged author, or authors, of the threat where such an author is, or authors are, expressly indicated in the communication by the submitting Member State(s). Where no such author is indicated in the communication, “Not indicated” is recorded.
Nature of the Alleged Author(s) of the Threat (If Any Indicated)
This column records the nature — whether State(s), non-state actor(s), or both State(s) and non-state actor(s) — of the alleged author, or authors, of the threat where such an author is, or authors are, expressly indicated in the communication by the submitting Member State(s). With respect to the nature of the author(s) of the alleged threat giving rise to the claim of self-defense, the catalogue distinguishes between three sets of categories: (1) A State (or States); (2) non-state actors; or (3) both a State (or States) and non-state actors.
In respect of certain communications, difficulties arose in classifying a particular alleged author as either State or non-state in character. For example, in S/1998/934 (Iran) Iran refers to the alleged author of the threat as the “Taliban militia,” whereas in S/2001/946 (United States) the United States refers to the “Taliban regime.”
It is also important to bear in mind that, in respect of certain communications, it is not necessarily clear whether or not the State submitting the communication intended to attribute the allegedly self-defense-generative conduct of relevant non-state actors (for example, a purported “armed attack” by alleged “terrorists” or “irregular forces”) to a State (for example, to the State from whose territory those actors are allegedly launching actions giving rise to a purported exercise of the right of self-defense of the victim State) or to otherwise seek to engage the responsibility of another State (for example, on the grounds that the other State allegedly acquiesced in or otherwise tolerated self-defense-generative conduct of the non-state actors).
Summary of Self-defense Alleged Grounds
This column provides a thumbnail sketch of the grounds — as alleged by the Member State(s) submitting the communication — on which that State (or those States) could take measures in purported exercise of the right of self-defense. As a matter of emphasis, it is noted that the summary is not meant to exhaustively catalogue all of the alleged grounds (where more than one ground is alleged), but rather to merely give a gist of the complaint.
Regarding punctuation: as used in this column, the “¶” symbol indicates a paragraph break in the original communication; the “¶¶” symbol indicates a double-paragraph break in the original communication; and the “¶…¶” symbol indicates a break spanning more than two paragraphs in the original communication.
UNSC Meeting(s) (If Any) at Which the Comm. was Raised
This column records the meetings of the Security Council, if any, at which the communication was expressly discussed or the conduct underlying the communication was otherwise raised. To help identify meetings, both the U.N. symbol (for example, “S/PV.2247”) and the number of the meeting (for example, “2247th”) are recorded. Researchers sought to identify such meetings by searching for the Security Council symbol of the communication via online Council meeting records. However, the results in this column should be considered preliminary, due, in part, to the low quality of some online meeting records and to the lack of reliable records extending back to the establishment of the Security Council.
Responsive Act (If Any) by the UNSC
This column records the formal responses, if any, of the Security Council in respect of each submitted communication, as identified by researchers. For the purposes of this column, a formal response could include only either (i) an adoption of an act of the Security Council that included a relevant provision (or provisions) or (ii) the issuance of a presidential statement that contained a relevant provision (or provisions). However, the results in this column should be considered preliminary, due, in part, to the low quality of some relevant records.
Where a resolution of the Security Council is recorded, the relevant portion is excerpted verbatim, followed by an indication of the vote pertaining to the resolution.
UN Repertory Inclusion?
This column records whether a communication was or was not found by a researcher to be referenced in the Repertory of the Practice of United Nations Organs or a Supplement thereto. To make this assessment, a search of the communication’s Security Council symbol was made in the online version of the Repertory and Supplements thereto. If the communication was found to be included in the Repertory or a Supplement thereto, the relevant part(s) and/or article(s) — for example, “Chapter VII,” “Article 2(4),” and/or “Article 51” — were also recorded. If no such result was identified, “None identified” is recorded. However, the results in this column should be considered preliminary, due, in part, to the low quality of some relevant records and to inconsistent reporting of relevant materials in the Repertory and Supplements thereto.
UNSC Repertoire Inclusion?
This column records whether a communication was or was not found by a researcher to be referenced in the Repertoire of the Practice of the Security Council or a Supplement thereto. To make this assessment, a search of the communication’s Security Council symbol was made in the online version of the Repertoire and Supplements thereto. If the communication was found to be included in the Repertoire or a Supplement thereto, the relevant part(s) and/or article(s) — for example, “Chapter VII,” “Article 2(4),” and/or “Article 51” — were also recorded. If no such result was identified, “None identified” is recorded. However, the results in this column should be considered preliminary, due, in part, to the low quality of some relevant records and to inconsistent reporting of relevant materials in the Repertory and Supplements thereto.
URL to an English Text
This column records a source uniform record locator (URL) where the English text, whether in its original submission or through a U.N. translation (the latter for communications submitted in a language other than English), of the report was found.
Note that to access certain URLs, a live session of the ODS website may need to already be open and current in the browser: https://documents.un.org.
URL to Non-English Original Text (If Any)
Several reports were communicated in languages other than English. This column records, where applicable, a URL for each communication originally made — in whole or in part — in a language other than English. That URL is derived from the link provided via a search for the report in the ODS.
For some communications, part of the report is expressed in one language whereas another part of the report is expressed in another language. In respect of certain reports, two original languages are listed. For certain reports, the original-language text is not available via the ODS, even though translated versions are available; for those reports, “Not available” is recorded in this field.
Note that to access certain URLs, a live session of the ODS website may need to already be open and current in the browser: https://documents.un.org.
This column contains a Perma.cc link generated by a researcher of the web address of a version of the English text of the communication.
V. Credits; Feedback
The catalogue authors gratefully acknowledge the following people: Scott Anderson, Ashley Deeks, Mona Khalil, Eliav Lieblich, Marko Milanovic, Tom Ruys, Stephen Townley, and Larissa van den Herik, as well as participants in the 2018–2019 informal “International Law Lunches” hosted in collaboration with the Permanent Missions to the United Nations in New York of Belgium, Liechtenstein, Mexico, Norway, and Switzerland, for discussion and feedback; and Jennifer Allison, Bridget J. Reischer, and Caroline Walters of the Harvard Law School (HLS) Library, as well as other members of the HLS Library staff, for research support.
HLS PILAC receives generous support from the Swiss Federal Department of Foreign Affairs (FDFA). Any views expressed in this catalogue should not be taken, in any way, to reflect the official opinion of the Swiss FDFA or any entity other than the named HLS PILAC research team. HLS PILAC is grateful for the support that the Swiss FDFA provides for independent research and analysis. The research undertaken by the authors of this catalogue was independent; the views and opinions reflected in this catalogue are those solely of the authors; and the authors alone are responsible for any errors.
HLS PILAC is releasing the catalogue under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) license.
The research team invites critical feedback on the catalogue. We are particularly interested in finding ways to make the catalogue more useful for practitioners and researchers and in ensuring that the catalogue is as comprehensive and accurate as possible. Please send updates, emendations, suggestions, and other feedback to firstname.lastname@example.org with “Self-defense Catalogue” in the subject-line of the e-mail.
[Editor’s note: the Google Sheets version of the catalogue is below. And here are links to all of the versions of the catalogue itself:
. All of the contributors were, at the time that they contributed to the catalogue, students at Harvard Law School and research assistants at HLS PILAC.
. Nevertheless, the research team drew on important earlier efforts to identify “article 51 communications,” including the following: Repertoire of the Practice of the Security Council and subsequent Supplements thereto, http://www.un.org/en/sc/repertoire/, permalink: https://perma.cc/KZ3D-8U44; Repertory of the Practice of the United Nations Organs and Supplements thereto, http://legal.un.org/repertory/, permalink: https://perma.cc/2KFM-69ML; The procedure of the UN Security Council (Loraine Sievers & Sam Daws eds., 4th ed., 2014) and Supplements thereto, including https://www.scprocedure.org/chapter-7-section-12, permalink: https://perma.cc/8HZP-JQXX; https://www.scprocedure.org/chapter-7-section-12b, permalink: https://perma.cc/6UK5-HFT5; https://www.scprocedure.org/chapter-7-section-12g, permalink: https://perma.cc/83VL-4UCF; and, especially, https://docs.wixstatic.com/ugd/54a569_dee1a4ae43a74d6b92800bff6a225652.pdf, permalink: https://perma.cc/TH8Y-92CX; Digests of State practice collected in the Journal on the Use of Force and International Law; Christine Gray, International Law and the Use of Force (4th ed., 2018); Olivier Corten, Ius contra bellum, Positions exprimées à l’occasion de précédents particuliers, Centre de droit international de l’Université Libre de Bruxelles (undated), https://iusadbellum.wordpress.com/a-loccasion-de-precedents-particuliers/, permalink: https://perma.cc/PZ3S-9W98; James A. Green, The article 51 reporting requirement for self-defense actions, 55 Virginia J. Int’l L. 563 (2015); Olivier Corten, The Law Against War (2012); D.W. Greig, Self-Defence and the Security Council: What Does Article 51 Require?, 40 Int’l & Comp. L. Q. 366 (1991); Jean Combacau, The Exception of Self-Defense in U.N. Practice, in The Current Legal Regulation of the Use of Force 9–38 (Antonio Cassese ed., 1986).
. Under article 111 of the U.N. Charter, the Chinese, French, Russian, English, and Spanish texts are equally authentic. See U.N. Charter art. 111. The text of article 51 in those languages is as follows: French: “Aucune disposition de la présente Charte ne porte atteinte au droit naturel de légitime défense, individuelle ou collective, dans le cas où un Membre des Nations Unies est l’objet d’une agression armée, jusqu’à ce que le Conseil de sécurité ait pris les mesures nécessaires pour maintenir la paix et la sécurité internationales. Les mesures prises par des Membres dans l’exercice de ce droit de légitime défense sont immédiatement portées à la connaissance du Conseil de sécurité et n’affectent en rien le pouvoir et le devoir qu’a le Conseil, en vertu de la présente Charte, d’agir à tout moment de la manière qu’il juge nécessaire pour maintenir ou rétablir la paix et la sécurité internationales.”; Russian: “Настоящий Устав ни в коей мере не затрагивает неотъемлемого права на индивидуальную или коллективную самооборону, если произойдет вооруженное нападение на Члена Организации, до тех пор пока Совет Безопасности не примет мер, необходимых для поддержания международного мира и безопасности. Меры, принятые Членами Организации при осуществлении этого права на самооборону, должны быть немедленно сообщены Совету Безопасности и никоим образом не должны затрагивать полномочий и ответственности Совета Безопасности, в соответствии с настоящим Уставом, в отношении предпринятия в любое время таких действий, какие он сочтет необходимыми для поддержания или восстановления международного мира и безопасности.”; Spanish: “Ninguna disposición de esta Carta menoscabará el derecho inmanente de legítima defensa, individual o colectiva, en caso de ataque armado contra un Miembro de las Naciones Unidas, hasta tanto que el Consejo de Seguridad haya tomado las medidas necesarias para mantener la paz y la seguridad internacionales. Las medidas tomadas por los Miembros en ejercicio del derecho de legítima defensa serán comunicadas inmediatamente al Consejo de Seguridad, y no afectarán en manera alguna la autoridad y responsabilidad del Consejo conforme a la presente Carta para ejercer en cualquier momento la acción que estime necesaria con el fin de mantener o restablecer la paz y la seguridad internacionales.”; Chinese: 联合国任何会员国受武力攻击时，在安全理事会采取必要办法，以维持国际和平及安全以前，本宪章不得认为禁止行使单独或集体自卫之自然权利。会员国因行使此项自卫权而采取之办法，应立向安全理事会报告，此项办法于任何方面不得影响该会按照本宪章随时采取其所认为必要行动之权责，以维持或恢复国际和平及安全.
. Pursuant to rule 6 of the Provisional Rules of Procedure of the Security Council, “[t]he Secretary-General shall immediately bring to the attention of all representatives on the Security Council all communications from States, organs of the United Nations, or the Secretary-General concerning any matter for the consideration of the Security Council in accordance with the provisions of the Charter.” Provisional Rules of Procedure of the Security Council, S/96/Rev.7, 1983, 2.
. See Green, above note 342, at 568–69, 603.
. In English, the denomination “reports” or “communications” might be preferred to “letters” for two reasons. First, “reports” and “communications” both encompass not only letters, strictly defined, but any other type of document irrespective of its designation. Second, “reports” and “communications” both also appear to encompass verbal statements that are made in order to bring to the attention of — in the broad sense of communicating to — the Council measures taken in purported exercise of the right of self-defense. That broader approach seems to align more closely with the equally authentic French text (“portées à la connaissance du Conseil de sécurité”) and Spanish text (“serán comunicadas … al Consejo de Seguridad”). However, as noted below, it is not clear whether verbal statements alone — that is, without an accompanying written submission — would suffice to satisfy the reporting requirement laid down in the second sentence of article 51. In any event, per Green, “reports” might be something of a misnomer itself. See Green, above note 342.
. See Military and Paramilitary Activities, Judgment, above note 148, at 120–23.
. See U.N. Official Documents System, https://documents.un.org/, permalink: https://perma.cc/9SH8-ULHY.
. See United States, S/2016/869 (Oct. 17, 2016) (“These actions were taken with the consent of the Government of Yemen. Although the United States therefore does not believe notification pursuant to Article 51 of the Charter of the United Nations is necessary in these circumstances, the United States nevertheless wishes to inform the Council that these actions were taken consistent with international law.”).
. See above note 342 for a list of additional resources consulted.
. However, in a handful of cases, the ICJ has expressed its perspective regarding certain aspects of the article-51-reporting requirement, including in respect of the requirement’s material and temporal scope, its legal nature, and certain consequences that may, in the Court’s view, arise (or inferences that may be drawn) from an absence of reporting — or at least excerpted self-defense communications made to the Security Council. Those cases include Military and Paramilitary Activities, Judgment, above note 148, at 105, 120–23; Nuclear Weapons, Advisory Opinion, above note 179, at 245; Oil Platforms (Iran v. U.S.A.), Judgment, 2003 I.C.J. Reports, 161, 185, 193–94 (Nov. 6); Armed Activities on the Territory of the Congo (DRC v. Ug.), Judgment, 2005 I.C.J. Reports,168, 222 (Dec. 19). See also Military and Paramilitary Activities, Judgment, above note 148, Dissenting Opinion of Judge Schwebel, 373–377. See further EECC, Partial Award, Jus Ad Bellum—Ethiopia’s Claims 1–8, para. 11 https://pcacases.com/web/sendAttach/763, permalink: https://perma.cc/VN5X-3X6N.
. The following are some of the examples of communications that were not included in the catalogue because they were not considered to report measures that had already been taken: Argentina, S/14961 (Apr. 9, 1982); Yugoslavia, S/1999/322 (Mar. 24, 1999); Liberia, S/2001/562 (June 6, 2001); Democratic Republic of the Congo, S/2002/286 (Mar. 18, 2002); Democratic Republic of the Congo, S/2004/489 (June 14, 2004); Israel, S/2006/515 (July 12, 2006); Azerbaijan, S/2008/82 (Feb. 8, 2008); Sudan, S/2012/277 (Apr. 30, 2012); Democratic People’s Republic of Korea, S/2013/50 (Jan. 24, 2013).
. In the words of Professor Green: “reports that were submitted prior to force being used in self-defence (or, in some cases, prior to the expected exercise of defensive force that was ultimately never used).” Green, above note 342, at 599 (emphasis added). See further id. at 599–602.
. See, e.g., Pakistan, S/25860 (May 28, 1993); Israel, S/2006/1029 (Dec. 26, 2006); Israel, S/2007/285 (May 16, 2007); and Iran, S/2008/377 (June 10, 2008). See also Israel, S/2006/891 (Nov. 15, 2006); Israel, S/2007/733 (Dec. 13, 2007). Israel, S/10244 (June 30, 1971) was not included because it seemed to imply — but did not clearly report — self-defense measures, thus raising a similar interpretative issue. See further, e.g., Cyprus, S/20893 (Oct. 10, 1989); Lebanon, S/1994/954 (Aug. 9, 1994); Iraq, S/2001/805 (Aug. 20, 2001); Pakistan, S/2002/571 (May 22, 2002).
. See, e.g., Iraq, S/2001/152 (Feb. 21, 2001); Democratic Republic of the Congo, S/2002/286 (Mar. 18, 2002).
. See, e.g., Russia, S/2002/1012 (Sept. 12, 2002); Israel, S/2006/515 (July 12, 2006).
. See, e.g., United Kingdom, S/14964 (Apr. 11, 1982); United Kingdom, S/14997 (Apr. 24, 1982); United Kingdom, S/15006 (Apr. 28, 1982); United Kingdom, S/15010 (Apr. 29, 1982); Argentina, S/15018 (Apr. 30, 1982); United Kingdom, S/15058 (May 8, 1982); Rwanda, S/1994/586 (May 17, 1994); Iraq, S/2001/805 (Aug. 20, 2001); Israel, S/2009/131 (Mar. 6, 2009); Israel, S/2009/493 (Oct. 2, 2009); Israel, S/2012/69 (Jan. 27, 2012).
. See, e.g., Armenia, S/26394 (Sept. 1, 1993), at 2 (Armenia communicating “countermeasures” taken by “the Self-Defence forces of Nagorny Karabakh” in response to alleged attacks by Azerbaijani military units).
. See Military and Paramilitary Activities, Judgment, above note 351, at 35.
. See, e.g., (Draft) I.O. Responsibility Articles art. 42(2), above note 138, at 71 (“In the practice relating to United Nations forces, the term ‘self-defence’ has often been used in a different sense, with regard to situations other than those contemplated in Article 51 of the Charter of the United Nations. References to ‘self-defence’ have been made also in relation to the ‘defence of the mission’. For instance, in relation to UNPROFOR, a memorandum of the Legal Bureau of the Canadian Department of Foreign Affairs and International Trade held that “‘[s]elf-defence’ could well include the defence of the safe areas and the civilian population in those areas.’ While these references to ‘self-defence’ confirm that self-defence represents a circumstance precluding wrongfulness of conduct by an international organization, the term is given a meaning that encompasses cases other than those in which a State or an international organization responds to an armed attack by a State. In any event, the question of the extent to which United Nations forces are entitled to resort to force depends on the primary rules concerning the scope of the mission and need not be discussed here.”). For an array of contemporary perspectives concerning another possibly relevant concept — namely, “soldier self-defense,” including whether it may or may not fall within this right — see Elvina Pothelet & Kevin Jon Heller, Symposium on Soldier Self-Defense and International Law: Highlighting and Framing the Issue, Opinio Juris, Apr. 19, 2019, http://opiniojuris.org/2019/04/29/symposium-on-soldier-self-defense-and-international-law-highlighting-and-framing-the-issue, permalink: https://perma.cc/7JX5-KFHC (framing the symposium and providing links to its eight contributions to it).
. For example, People’s Republic of China to China; Democratic Kampuchea and Democratic Republic of Kampuchea to Kampuchea [Cambodia]; Federal Republic of Yugoslavia to Yugoslavia; Kingdom of the Netherlands to the Netherlands; Islamic Republic of Iran to Iran; Libyan Arab Jamahiriya to Libya; Republic of Vietnam to South Vietnam; Russian Federation to Russia; Syrian Arab Republic to Syria; United Kingdom of Great Britain and Northern Ireland to United Kingdom; United States of America to United States; Viet Nam, Viet-nam, and Viet-Nam to Vietnam.
. Iran, S/1998/934 (Oct. 8, 1998).
. United States, S/2001/946 (Oct. 7, 2001), at 1.
. See, e.g., Qatar, Saudi Arabia, the United Arab Emirates, and Kuwait, S/2015/217 (Mar. 27, 2015) (letter and annex in English and enclosure in Arabic).
. See, e.g., China, S/13294 (May 3, 1979) (listing “CHINESE/ENGLISH” as the original language).
. See, e.g., Iraq, S/17450 (Sept. 10, 1985) (the Arabic original is not available via ODS whereas the Chinese, English, French, Russian, and Spanish versions are available), https://documents.un.org/prod/ods.nsf/xpSearchResultsM.xsp, permalink: https://perma.cc/T2VK-MQ2L.
. See Perma.cc, About Perma.cc, https://perma.cc/about, permalink: https://perma.cc/BAA5-P2KG (“When a user creates a Perma.cc link, Perma.cc archives the referenced content and generates a link to an archived record of the page. Regardless of what may happen to the original source, the archived record will always be available through the Perma.cc link. ... [¶] Perma.cc is developed and maintained by the Harvard Law School Library in conjunction with university law libraries across the country and other organizations in the ‘forever’ business.”).