First, European traditions and experience in international law and organization since the 16th century had a significant impact on the creation of an international organization in the 20th century. Second, the UN also evolved out of the Concert of Europe that was created by the Congress of Vienna in 1815. On the one hand, the Concert of Europe was dominated by the great powers, which acted as the guardians of the modern state system (Alger, 1995: 4). On the other hand, meeting more than 30 times between 1815 and 1878 to settle common issues and coordinate their actions, these same powers had also set practices and principles such as multilateral consultation, collective security, and special status for powerful countries that are still influential in the UN system today (Mingst and Karns, 2012:19). Third, the origins of the UN system can be also traced to The Hague Conferences, a pair of international meetings that were held in 1899 and 1907. The Hague system codified procedures for the prevention of war and the pacific settlement of conflicts, which extensively influenced the UN (Alger, 1995: 5). The Hague system also created techniques and practices such as arbitration, negotiation, legal recourse as well as significant legal regulations and institutions including the Convention for the Pacific Settlement of International Disputes, ad hoc commissions of inquiry, and the Permanent Court of Arbitration. More importantly, The Hague Conferences contributed to the formation of the UN by establishing and reinforcing the principles of universality and legal equality, because both non-European states and relatively small states were included among the participants (Mingst and Karns, 2012:20). Fourth, the international bodies or international public unions were already established in the 19th century to settle common technical issues stemming from modern developments in communication, health, commerce, railroads, and agriculture. Growing out of the Industrial Revolution, they formed another example of early transnational integration and led to the creation of international public unions such as the Rhine Commission (1815), the Danube Commission (1848), the International Telegraphic Union (1865), and the Universal Postal Union (1874). (Alger, 1995:5) These international bodies solidified a group of permanent bureaucrats called international secretariats to implement specific tasks on a regular basis. Moreover, these organizations were also instrumental in creating methods for multilateral conventions, treaties, and international law (Mingst and Karns, 2012:20). Finally, the League of Nations, established after the end of World War I, had a huge impact on the creation of the UN. In fact, the UN can be defined as “a child of the League of Nations” (Alger, 1995:4). The League provided a model for the normative and institutional structure of the UN. It is a fact that the UN derived important organizational features from the League such as the Secretariat and Assembly. By including other international agencies such as the International Labour Organization (ILO) and the Permanent Court of International Justice (PCIJ), the League also set a precedent for the UN (Hanhimaki, 2008: 10). The UN also seemed to have learnt from both the failures and achievements of the League. For instance, because the League had failed to prevent the aggressions of Italy and Japan in the 1930s, the architects of the UN altered the unanimity rule, which had been required in the League to deploy military forces in response to aggression (Alger, 1995:4). 

The UN Charter also shared the ideals and many structural elements on which the League was built. The most remarkable example was that both organizations identified the promotion of international security and the peaceful settlement of disputes as their key goals. The UN has put more emphasis on the economic and social progress of nations than the League, because the Great Depression of the late 1920s was considered the root cause of World War II. As such, in the UN system the economic and social progress of societies has been appreciated for sustaining international security. In order to prevent another devastating war, the founders of the UN defined international security in a broader sense and sought to enable the UN to become active in international politics. Therefore, they identified key areas of the UN as military security, economic and social development, human rights, and international justice (Hanhimaki, 2008: 15- 16). Although the League failed to prevent the outbreak of World War II, the idea of creating an international organization to protect international peace never faded (Mingst and Karns, 2012:21- 22). In fact, the War strengthened the efforts to construct a stronger collective security mechanism at the international level. The UN was also a response to a radically transformed world politics in the wake of  World War II. While the European imperial powers collapsed, the US and Soviet Union emerged from the war as the two superpowers in international politics. Therefore, the UN was formed also to manage this changing international system and power relations between the superpowers as well as the blocs (Hanhimaki, 2008: 13). 

The first concrete step toward establishing the UN was taken when U.S. President Roosevelt and British Prime Minister Winston Churchill signed a joint declaration called the Atlantic Charter in August 1941.The Atlantic Charter paved the way for the Declaration by United Nations that was signed in January 1942 by twenty-six nations fighting against the Axis powers. The declaration was not only the first official document that included the term ‘United Nations’ but also reaffirmed the commitment of these states to the principles of the Atlantic Charter (Bennett, 1995: 47).

Similar to the League system, the General Assembly is the only UN body where all member states are equally represented. In other words, regardless of their size or power, each member state has only one vote. Compared to the Security Council, where the P5 states have veto rights, the General Assembly is considered to be relatively a democratic UN organ due to its “one state- one vote” formula and the majority rule in its decision-making process. As such, the General Assembly is based on the principle of the sovereign equality of states. Nevertheless, this does not mean that all states are equal in terms of their economic, political, or military power (Hurd, 2014: 106 and 115).

According to Article 4(2), the General Assembly is authorized to approve the admission of any new state to the UN membership upon the recommendation of the Security Council. Currently, in addition to 193 member states, two states in the UN have “non-member observer status.” Besides the Holy See (Vatican), the General Assembly granted Palestine the non-member observer status in December 2012 by adopting the Resolution 67/19 on “the Status of Palestine in the United Nations” with 138 votes in favor, 9 against, and 41 abstentions.

The General Assembly has subsidiary organs such as boards, commissions,committees, councils, panels, and working groups. The majority of its work takes place in six main committees, each of which is responsible for a specific topic. The First Committee deals with disarmament and international security; the Second Committee with economic and financial matters; the Third Committee with social, humanitarian and cultural matters; the Fourth Committee with special political and decolonization matters, the Fifth Committee with administrative and budgetary questions; and the Sixth Committee with legal matters. 

The General Assembly also fulfills important elective functions. The General Assembly has the authority to elect the non-permanent members of the UNSC, all members of the ECOSOC, and non-administering members of the Trusteeship Council. The General Assembly has a joint responsibility with the Security Council for the election of judges to the ICJ, the appointment of the Secretary-General, and the admission of new states to UN membership (Bennett, 1995:66).

The General Assembly has also several significant powers and functions. The most significant function of the General Assembly is to consider and make recommendations on any subject. Article 10 mandates the General Assembly to discuss any matter within the scope of the Charter. However, its recommendations are non-binding on member states (Bennett, 1995:65). Its agenda has expanded over the years. The items on its agenda include conflict situations, development, poverty, human rights, global warming, international justice, and administrative and financial matters (Karns, Mingst, and Stiles, 2015:113)

Another function of the General Assembly is to operate as a central coordinating body among other UN bodies and agencies. The Assembly reviews annual reports sent from other principal UN organs—namely, the UNSC, the ECOSOC, and the Trusteeship Council. In addition, it receives periodic reports from other UN agencies (Bennett, 1995:65). 

The General Assembly also has a mandate to consider and approve the budget of the UN and apportion the expenses among member states. The Assembly is authorized to consider and approve financial and budgetary arrangements for specialized agencies (Article 17). The UN budget is the only issue on which the General Assembly can take binding decisions. Finally, the General Assembly and the Security Council also have joint responsibility for revision to the UN charter. The General Assembly can propose amendments by a two-thirds majority.The General Assembly and the Security Council also have the authority to call for a general conference to revise the Charter.

General Assembly resolutions serve as an important source of the UN’s normative influence around the world. First, its statements and resolutions serve a significant norm-creating function. Second, they contribute to the legitimization of new ideas and policies (Hurd, 2014:110) 

Article 11 of the Charter authorizes the General Assembly to consider the general principles regarding the maintenance of international peace and security and make recommendations. The General Assembly can also discuss any question related to the maintenance of international peace and security that are brought by a member state or by the Security Council and make recommendations to the concerned parties or the UNSC.

One exception is the provision of Article 12. If the UNSC is exercising its functions with regard to any dispute or situation, the General Assembly is not allowed to make recommendations about that situation without the request of the UNSC. On the other hand, the General Assembly can call the attention of the UNSC to situations that may endanger international security. However, General Assembly resolutions are recommendations and therefore not legally binding. Because of this, some scholars argue that the Assembly’s power, although broad, is “shallow” (Hurd, 2014:108).

The UN Security Council is the central organ in the UN system. The primary responsibility of the UNSC is the maintenance of international peace and security. The UNSC therefore has broad powers: it can investigate disputes that may pose a threat to international peace and security, and make recommendations toward resolving disputes peacefully. The Security Council has also powers to take diplomatic or economic measures against an aggressor state. Most importantly, it can authorize military action (Bookmiller, 2008: 54). 

Together with the General Assembly, the UNSC takes part in the election of the UN Secretary-General, judges to the ICJ, and new members of the UN.

The Security Council has no regular meeting schedule. It is in permanent session to meet at any time so as to respond effectively to international conflicts and crises.

The UN Secretariat is considered the ‘second UN’ and has the capacity to exercise significant influence over the UN itself and occasionally on member states (Karns, Mingst, and Stiles, 2015:134).

The UN Secretariat comprises a series of offices and departments, each of which is headed by an undersecretary-general. Their work involves the implementation of the economic, humanitarian, and social programs that aim to fulfill the Charter’s promises. Several departments are responsible for the conduct of UN peace operations. The Secretariat also undertakes technical tasks such as data collection, research, documentation, and translation (Mingst and Karns, 2012: 39).

Chapter XV of the UN Charter clearly identifies the main tasks that the Secretary General must fulfill:
• To act as the chief administrative officer of the organization,
• To act as the secretary in all meetings of the other principal organs of the UN,
• To perform other functions tasked by these UN bodies,
• To make an annual report to the General Assembly on the work of the UN,
• To bring to the attention of the Security Council matters that may threaten international peace and security,
• To appoint the UN staff under regulations established by the General Assembly.

As the chief diplomat, for instance, the Secretary-General also acts as mediator in conflicts between the member states. Together with the secretariat, the Secretary General also proposes new agenda items on issues ranging from the environment to education for deliberation in UN bodies (Bookmiller, 2008:62).

The ICJ has two main functions: first, the court settles legal disputes between states. This kind of cases before the court is called contentious cases. Second, the court is authorized to give advisory opinions on legal questions upon request (Doğan,2014:133). The ICJ can also hear specific cases on legal disputes referred to it by states. Only states can bring cases before the court. In other words, non-state actors such as citizens, non-governmental organizations, or businesses cannot sue or be sued (Bookmiller, 2008:65). As such, the ICJ cannot settle disputes between states and non-state actors. The court may also issue advisory opinions on legal questions referred to it by authorized UN organs and agencies including the General Assembly and Security Council.

ECOSOC is the principal UN organ responsible for addressing international economic and social programs. Considered the most complex body of the UN system, the council aims to promote the welfare of the individuals, find solutions to global economic, social and health problems, and support human rights (Karns, Mingst, and Stiles, 2015: 129).

The Charter mandates ECOSOC to initiate studies and reports on economic, social, cultural, educational, health, and related topics, and make recommendations regarding such issues to the General Assembly. It can also recommend measures for promoting respect for human rights and fundamental freedoms.

ECOSOC holds an annual meeting in New York or Geneva to discuss economic and social issues. ECOSOC does not have binding power upon member states, but it plays a coordinating role between specialized agencies and programs. It generates a globally normative and political influence and increases world-wide awareness through high-profile international meetings and sponsoring research on related topics (Hurd, 2014:111). Bennett divides the main functions of ECOSOC into three categories: a) deliberation and recommendations, b) research and reports, c) coordination (1995:71). ECOSOC mainly oversees and coordinates diverse agencies, commissions, committees, funds, and programs within the UN system. In this regard, the first group consists of eight functional commissions, five regional commissions, and other bodies. Because the Commission on Sustainable Development had been abolished in 2012, the number of functional commissions decreased from nine to eight. The first group organs are directly tied to ECOSOC. The second group includes 19 specialized agencies, including the World Bank, the International Monetary Fund (IMF), and World Health Organization. These agencies operate independently from ECOSOC. In the third group, there are programs and funds established by the General Assembly such as the UN Development Program (UNDP), the Office of the UN High Commissioner for Refugees (UNHCR), and the UN Children’s Fund (UNICEF). (Aslan and Aslan, 2014:99) These programs and funds submit reports to both the General Assembly and ECOSOC. The latter also has the authority to oversee the implementation of the Covenant on Economic, Social and Cultural Rights (Pease, 2012: 271).

The Trusteeship Council, another principal organ of the UN, was established to oversee the administration of trust territories. The council was authorized to examine reports about the political, social, economic, educational development of colonial people and send special missions to these regions. The main objective of the council was to promote the decolonization process after World War II. It supervised the transition of 11 trust territories toward independence.

While it exists officially, the council is no longer an active UN body. “The Trusteeship Council, by amending its rules of procedure, will now meet as and where occasion may require” (www.un.org).

• To maintain international peace and security,
• To develop friendly relations among nations based on respect for the principle of equal rights and self-determination of peoples,
• To encourage respect for human rights and for fundamental freedoms for all without distinction as to race, sex, language, or religion
• To be a center for harmonizing the actions of nations.

First and foremost, the UN Charter establishes the sovereign equality of its members as the most fundamental principle upon which the UN is founded. Equality here means that all states are equal in terms of their legal status rather than their size, population, or political and economic power. As mentioned earlier, the “one state/one vote” rule in the General Assembly is based on this very principle of states’ sovereign equality. On the other hand, the design of the UNSC with its permanent membership and veto system reflects the power distribution and inequality among nations (Karns, Mingst, and Stiles, 2015:118).

The key principles of the UN underline the maintenance of international peace and security as the primary goal. Toward this goal, two principles gain prominence. The first is the prohibition of the threat or use of force. Article 2(4) clearly states that “all members shall refrain in their international relations from the threat or 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” (UN Charter, 1945:3). This provision, which aims to ensure all states to act in accordance with international peace and security, is binding upon both member states and non-member states.
The second principle related to international peace and security is the peaceful settlement of international disputes. Article 2(3) provides that all members shall settle their international disputes through peaceful means so that they do not endanger international peace and security. Article 32(3) of the Charter also authorizes the UNSC to encourage regional arrangements (institutions) and individual states to promote the pacific settlement of local disputes. In addition, member states are obliged to support the enforcement actions of the UN and refrain from giving assistance to states against which such actions are taken. Moreover, all members have an obligation to “fulfill in good faith all the obligations assumed by them in accordance with the Charter” (Karns, Mingst, and Stiles, 2015:110).

The only exception to the prohibition of the use of force is provided in Article 51 of the Charter. Article 51 establishes the right to self-defense of a state against armed attack. In case of armed attack, member states have the inherent right of individual or collective self-defense until the UNSC takes necessary measures. Members are obliged to immediately report their measures to the UNSC. However, such measures taken by member states under the right of self-defense cannot prevent the UNSC to take necessary measures for the maintenance of international peace and security. Given the history of international relations, it is not easy to establish which state has the right to self-defense and which state is the aggressor or victim in each and every case, because states have no consensus on the definition of aggression and attack (Mingst and Karns, 2012:24).

The Charter clearly prohibits the organization from intervening in matters that are essentially under the domestic jurisdiction of any state. The only exception is the application of enforcement measures taken by the UNSC. However, the distinction between the domestic affairs and international affairs is not that clear and this makes this principle of “non-interference” quite controversial (Bennett, 1995:60). More importantly, this creates a great dilemma between state sovereignty and the protection of human rights. Particularly in the case of gross and systemic human rights violations, humanitarian intervention has generated a controversial debate in recent international politics (Pease, 2012: 275). On the other hand, because the respect and promotion of human rights is one of the major goals of the UN, there have also been efforts such as the endorsement of “responsibility to protect” (R2P) to secure a reconciliation between these basic principles and the protection of human rights.

Global security governance constitutes a significant aspect of the UN’s responsibility and activities. Global security governance consists of a wide range of activities and issues, from controlling the flow of small arms and inspecting weapons of mass destruction to peacekeeping and peace-enforcement missions. Although the UNSC is the central authority, these activities involve various types of actors at different levels from the local to the international. The main problem concerning global security governance stems from the coordination of diverse activities of various actors (Weiss and Thakur, 2010:4).

The operational contribution of the UN involves concrete activities in preventing, settling, managing, and resolving conflicts. In this regard, the organization has developed several instruments throughout its history such as the pacific settlement of disputes, peacekeeping and peacebuilding, and peaceenforcement. These instruments are designed so as to make sure that states fulfill their obligations under the UN Charter and that the UN take the necessary measures if states fail to comply with the Charter (Hurd, 2014: 138).

The pacific settlement of disputes is defined as the ‘diplomatic’ instrument of the UN that aims to help conflicting parties solve their disputes through peaceful and non-coercive means (Dogan, 2012: 131). The UN employs different techniques, including mediation, good offices, special envoys and missions as well as preventive diplomacy (Mingst and Karns, 2012:102).

Peacekeeping emerged as an innovation of the organization to adapt itself to the changing security conditions of international politics. Under the Cold War circumstances, peacekeeping was regarded as the only “realistic operational function” of the organization in maintaining international peace and security (Dogan, 2012: 124). As such, peacekeeping was the UN’s main security activity during the Cold War years.

Peacekeeping involved the deployment of a military force in conflict zones to monitor a ceasefire or patrol a buffer zone between belligerents. All peacekeeping operations during the Cold War, with the exception of the mission to Congo (1960- 1964), were deployed in interstate conflicts based on the consent of conflicting parties as well as on principles such as the non-use of force except for self-defense, political neutrality, and international legitimacy (Diehl, ss.116-117).

Peacekeeping had significant purposes. Its main one was to contain a conflict and prevent it from escalating into a war, especially into a larger systemic war. In this regard, it has been a significant instrument toward maintaining international security. Through its peacekeeping missions, the organization succeeded preventing the interference of the superpowers in conflicts or the escalation of any military confrontation that might have endangered the world order (Dogan, 2012: 125).

Peacebuilding is a more ambitious policy agenda than peacekeeping, because it particularly focuses on intrastate conflicts. It is also a method for the governance of new security issues such as ethnic conflicts or civil wars, whose number has increased since the early 1990s. 

Peacekeeping missions differ from peace-enforcement in three aspects: first, peacekeeping is based on the consent of parties to the conflict. Second, they are politically neutral. Third, force can be used as a last resort and only for self-defense (Mingst and Karns, 2012: 112). Peace-enforcement missions, on the other hand, do not require the consent of target states or political neutrality. Most importantly, they involve collective military action against a state (Hurd, 2014: 138).

Normative contribution refers to the creation and promotion of new security norms and frameworks. It is directly related to the UN’s function of collective legitimization, which strengthens particular policies, positions of particular states, and particular values in international politics. In other words, collective legitimization highlights the UN’s capacity to legitimize or delegitimize norms in the international system (Dogan, 2012: 134-135). The development of the norm of R2P in the early 2000s clearly illustrates this function of the UN with regard to global security governance.

First, the work of the General Assembly is of great importance to the development of international law. Article 13 of the Charter mandates the General Assembly to initiate studies and make recommendations in order to encourage the development of international law and its codification. 

The General Assembly serves as a forum where member states negotiate and adopt multilateral conventions. Thus, its resolutions have gradually paved the way for the creation of new international treaties, agreements, and norms, and for enhancing the development of international law, including international humanitarian and human rights law. The legal work of the UN addresses a wide range of issues including environmental protection, drug trafficking, nuclear proliferation, migration, and terrorism (UN-C). 

Second, as the judicial arm of the UN, the work of the ICJ also contributes to global governance in several ways. The court provides states with an opportunity to settle their disputes through judicial means. For instance, the ICJ has been successful in solving some territorial issues such as the delimitation of the North Sea continental shelf, fisheries in the Gulf of Maine, and the maritime boundary between Cameroon and Nigeria. Moreover, since the ICJ Status mentions judicial decisions of the court among the secondary sources of international law, its advisory opinions and decisions are important for developing international law (Karns, Mingst, and Stiles, 2015:142).

Third, the UN has a leading role in the promotion of the rule of law and justice in post-conflict situations. In this regard, the UN has greatly encouraged the emergence of transitional justice, which includes both judicial and nonjudicial measures in addressing gross and systemic human rights violations after a period of oppression or armed conflict.

More importantly, the UN has a crucial operational function in supporting transitional justice mechanisms. First, in order to combat impunity and to ensure accountability for mass atrocities, the UN contributed to the promotion of international criminal justice by creating ad hoc and hybrid tribunals.

A truth commission is a temporary, nonjudicial body that investigates past human rights violation committed over a period of time. Truth commissions engage with victims, survivors, and perpetrators and aim to produce a final report on the patterns of human rights abuses. They are often authorized by a state (Hayner, 2011:11-12).

The UN bodies contribute to the governance of the international human rights regime in three main ways: (1) norm creation, (2) institutionalization, (3) monitoring and reporting. This is an analytical classification; in practice, these functions are intertwined.

The first obstacle is procedural. Amending the UN Charter is a difficult and complex process, because Charter amendments must be adopted by two-thirds majority of the General Assembly. These come into force when at least two thirds of member states, including all permanent members of the Security Council, ratify them in accordance with their own constitutional procedures. Second and more importantly, there are political obstacles stemming from the power politics of the international system. For instance, power politics as well as the NorthSouth divide create further complications.

• The General Assembly has no coercive or binding authority. It is the most democratic UN body where all member states have equal voting rights, but its decisions are “recommendations” to member states rather than legally binding directives (Hurd, 2014: 108). As such, critics argue that the General Assembly is a powerless UN body despite the fact that its resolutions reflect the will of the majority of its members.
• Its agenda items and decisions lack focus. For instance, the Assembly passed 239 resolutions in 2017 on a wide range of issues (General Assembly of the United Nations D). Many of these resolutions are defined as “ritual resolutions” that include similar texts on repeated items, and their content is formulated in general terms without paying due consideration to their implementation (Karns, Mingst, and Stiles, 2015: 122).
• The end of the Cold War has led to changes in the influence of the principal UN organs. The UNSC and Secretariat have gained prominence within the UN system and become the center of most UN activities. However, the importance of the General Assembly has declined (Mingst and Karns, 2012:30). While the General Assembly was able to take initiatives when the UNSC was paralyzed during the Cold War, it has taken a back seat since the early 1990s.

• One of the harsh criticisms leveled against the Council is that it privileges the five permanent members (which reflects the balance of power at the end of World War II) and so fails to represent the changing nature of the international system, particularly in the post-Cold War era (Hanhimaki, 2008: 33). Therefore, the structure of the UNSC is subject to numerous calls for reform.
• Due to the veto power of the five permanent members, the UNSC is regarded as an undemocratic body (Teixeira, 2003: 12). Thanks to its veto power, any permanent member can block the decision-making process in the Council. The conflicting interests of great powers often prevent the UNSC from taking necessary measures for the maintenance of international peace and security. The impasse at the UNSC with regard to the Syrian war illustrates this point. Although hundreds of thousands of people have been killed or wounded in the Syrian conflict, the international community has failed to stop it, mainly due to Security Council deadlocks.
• The UNSC does not fairly represent the majority of UN member states, especially since the organizational membership increased from 51 to 193. Indeed, the UNSC’s 15 members form only 7.7 percent of all UN members. More importantly, the P5 countries constitutes merely 2.6 percent of the total member states. Thus, only a limited number of states involve in taking significant decisions on international peace and security.
• The UNSC also fails in terms of geographical representation of the world. Northern and European countries have been overrepresented in the Council while those from Africa, Asia, and Latin America have been underrepresented. What is worse, there is not any African or Latin American state among the P5 (Karns, Mingst, and Stiles, 2015: 149). Greater financial contributions from states other than the permanent members also lead to questioning the legitimacy of the Council (Mingst and Karns, 2012: 32).