Background and creation In the century prior to the United Nation's creation, several international treaty organisations and conferences had been formed to regulate conflicts between nations, such as the
International Committee of the Red Cross and the
Hague Conventions of 1899 and 1907. Following the catastrophic loss of life in
World War I, the
Paris Peace Conference established the
League of Nations to maintain harmony between nations. The League successfully resolved some territorial disputes and created international structures for postal mail, aviation, and opium control, some of which were later absorbed into the UN. However, it lacked representation for colonial peoples – then half the world's population – and significant participation from several major powers, including the United States, the
USSR, Germany, and Japan. It failed to act against the 1931
Japanese invasion of Manchuria, the
Second Italo-Ethiopian War in 1935, the 1937
Japanese occupation of China, and Nazi expansions under
Adolf Hitler that escalated into World War II. ,
Franklin D. Roosevelt, and
Winston Churchill at the
Cairo Conference in 1943 ,
Franklin D. Roosevelt, and
Joseph Stalin at the
Yalta Conference, February 1945 On New Year's Day 1942, President
Franklin D. Roosevelt, Prime Minister
Winston Churchill,
Maxim Litvinov of the USSR, and
T. V. Soong of the
Republic of China signed a short document based on the
Atlantic Charter and the
London Declaration. The next day, representatives of 22 other nations added their signatures, and the document came to be known as the
United Nations Declaration. By 1 March 1945, 21 additional states had signed. The four major Allied countries – the United States, the United Kingdom, the Soviet Union, and the Republic of China – were styled the "
Four Powers" and became the foundation of the Security Council's executive structure. Following the 1943
Moscow Conference and
Tehran Conference, delegations from the Big Four met in mid-1944 at the
Dumbarton Oaks Conference in Washington, D.C., to negotiate the UN's structure. The composition of the Security Council quickly became the dominant issue. France, the Republic of China, the Soviet Union, the United Kingdom, and the United States were selected as permanent members; the United States attempted to add
Brazil as a sixth member but was opposed by the Soviet and British delegations. The most contentious question at Dumbarton Oaks and in successive talks was the veto rights of permanent members. The Soviet delegation argued that each permanent member should have an absolute veto that could block matters from even being discussed, whilst the British argued that nations should not be able to veto resolutions on disputes to which they were a party. At the
Yalta Conference of February 1945, the US, UK, and Russian delegations agreed that each of the Big Five could veto any action by the Council, but not procedural resolutions. On 25 April 1945, the
UN Conference on International Organization began in San Francisco, attended by 50 governments and a number of non-governmental organizations involved in drafting the
United Nations Charter. At the conference,
H. V. Evatt of the Australian delegation pushed to further restrict the veto power of permanent members, but his proposal was defeated twenty votes to ten, owing to fears that rejecting the strong veto would cause the conference to fail. The UN officially came into existence on 24 October 1945 upon ratification of the UN Charter by the five permanent members and a majority of the other 46 signatories. During the 1946–1951 period, it conducted sessions at the United Nations' interim headquarters in
Lake Success, New York, which were televised live on
CBS by the journalist
Edmund Chester in 1949.
Cold War in London, where the first Security Council meeting took place on 17 January 1946 The Security Council was largely paralyzed in its early decades by the
Cold War between the United States and the Soviet Union, and their respective allies; the Council was generally able to intervene only in conflicts unrelated to the superpower rivalry. A notable exception was the 1950 Security Council resolution authorizing a US-led coalition to repel the
North Korean invasion of South Korea, passed during a
Soviet boycott of the Council. In 1960, the UN deployed the
UN Operation in the Congo (UNOC) – the largest military force of its early decades – to restore order to the breakaway
State of Katanga, returning it to the control of the
Democratic Republic of the Congo by 1964. The Security Council found itself bypassed in favour of direct superpower negotiations during some of the decade's larger conflicts, such as the
Cuban Missile Crisis and the
Vietnam War. It focused instead on smaller conflicts without an immediate Cold War dimension, deploying the
UN Temporary Executive Authority in
West New Guinea in 1962 and the
UN Peacekeeping Force in Cyprus in 1964, the latter of which became one of the UN's longest-running peacekeeping missions. On 25 October 1971, over US opposition but with the support of many
Third World nations, the mainland
People's Republic of China replaced the
Republic of China in the Security Council seat; the vote was widely seen as a sign of waning US influence in the organization. With an increasing Third World presence and failures of UN mediation in the
Middle East,
Vietnam, and
Kashmir, the UN increasingly shifted its attention toward economic development and cultural exchange. By the 1970s, the UN budget for social and economic development far exceeded its budget for peacekeeping.
Post-Cold War holds a model vial of
anthrax while presenting to the Security Council in February 2003 After the Cold War, the UN saw a radical expansion in its peacekeeping duties, taking on more missions in ten years than it had in the previous four decades. Between 1988 and 2000, the number of adopted Security Council resolutions more than doubled, and the peacekeeping budget increased more than tenfold. The UN negotiated an end to the
Salvadoran Civil War, launched a successful
peacekeeping mission in Namibia, and oversaw democratic elections in post-
apartheid South Africa and post-
Khmer Rouge Cambodia. In 1991, the Security Council condemned the Iraqi
invasion of Kuwait on the same day of the attack and later authorized a
US-led coalition that successfully repulsed the Iraqi forces. Undersecretary-General
Brian Urquhart later described the hopes raised by these successes as a "false renaissance" for the organization, given the more troubled missions that followed. Though the Charter had been written primarily to prevent aggression by one nation against another, in the early 1990s the UN faced a number of simultaneous serious crises within states, including Haiti, Mozambique, and the former Yugoslavia. The
UN mission to Bosnia faced "worldwide ridicule" for its indecisive and confused response to ethnic cleansing. In 1994, the
UN Assistance Mission for Rwanda failed to intervene in the
Rwandan genocide amid Security Council indecision. In the late 1990s, UN-authorized international interventions took a wider variety of forms. The
UN mission during the 1991–2002
Sierra Leone Civil War was supplemented by British
Royal Marines, and the UN-authorized
2001 invasion of Afghanistan was overseen by
NATO. In 2003, the United States
invaded Iraq without a UN Security Council resolution authorizing the use of force, prompting renewed questioning of the Council's effectiveness. In the same decade, the Security Council deployed peacekeepers to address the
War in Darfur in Sudan and the
Kivu conflict in the Democratic Republic of the Congo. In 2013,
an internal review of UN actions in
the final battles of the
Sri Lankan Civil War in 2009 concluded that the organization had suffered "systemic failure".
21st century In 2011, the Security Council authorized a
no-fly zone over Libya during the
Libyan Civil War, under
Resolution 1973, which was adopted with ten votes in favour and five abstentions (Brazil, China, Germany, India, and Russia). Russia and China subsequently argued that the NATO-led intervention exceeded the resolution's mandate, and this experience shaped their approach to later crises: both vetoed multiple draft resolutions on the
Syrian civil war from 2011 onward, blocking efforts to impose sanctions or authorize force against the government of
Bashar al-Assad. The
Russian invasion of Ukraine in February 2022 precipitated a series of vetoes. Russia vetoed a draft resolution deploring the invasion on 25 February 2022, with eleven members voting in favour and China, India, and the United Arab Emirates abstaining. In September 2022, Russia again vetoed a resolution condemning its attempted annexation of four Ukrainian regions. These vetoes contributed to the adoption of
General Assembly Resolution ES-11/1, which deplored the invasion, and prompted the General Assembly to adopt Resolution 76/262 in April 2022, creating a standing mandate for a General Assembly debate whenever a veto is cast in the Security Council. The
Gaza war, which began in October 2023, produced further deadlock. The United States vetoed draft resolutions calling for an immediate humanitarian ceasefire in Gaza in October 2023, December 2023, and February 2024, arguing that they would undercut ongoing diplomatic negotiations. In 2024, seven draft resolutions were vetoed – the highest annual total since 1986 – including four by Russia, three by the United States, and one by China. == Role ==