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The United Nations

The United Nations emerged after World War II as an international peacekeeping organization. 


  • The United Nations (UN) was created at the end of World War II as an international peacekeeping organization and a forum for resolving conflicts between nations.
  • The UN replaced the ineffective League of Nations, which had failed to prevent the outbreak of the Second World War.
  • The UN was established on October 24, 1945, with headquarters in Manhattan, New York City, and reflected the rise of the United States to global leadership in the postwar period.

Negotiating a postwar world order

In 1944, delegations from the United States, the United Kingdom, the Soviet Union, and the Republic of China—four of the main Allied powers in World War II—met in Washington, DC to negotiate the parameters of the postwar world and to discuss the establishment of the international organization that would become known as the United Nations (UN).
Emblem of the United Nations. Image courtesy Wikimedia Commons.
The United Nations replaced the League of Nations, which had been created at the end of the First World War to provide states with an international forum for the peaceful resolution of disputes. Even though US President Woodrow Wilson was one of the key supporters of the League of Nations, the United States never officially joined the organization due to intense opposition from isolationist members of Congress. The League of Nations ultimately proved ineffective in preventing the outbreak of another world war and was formally dissolved in 1946.1
The United States played an instrumental role in the founding of the United Nations. The UN Charter, with its emphasis on peace, security, international law, economic development, and human rights, reflected the influence of US President Franklin D. Roosevelt and British Prime Minister Winston Churchill, who shared a vision for the postwar world.2 In 1941, the two leaders drafted the Atlantic Charter, which declared that there would be no territorial aggrandizement as a result of the war, that postwar international relations would be cooperative, and that disputes between states would be resolved through peaceful negotiation and not the use or threat of force. The Atlantic Charter eventually became the basis for the UN Charter.
The extent of US involvement in the creation of the United Nations, as well as the location of its main headquarters in New York City, demonstrates the rise of the United States to global leadership in the postwar period.3

The structure and function of the United Nations

The United Nations has several main bodies that serve different purposes. The Secretariat is the main administrative organ of the UN. It commissions research and applies the findings of studies to making the UN a more effective and efficient organization.
The General Assembly is the main deliberative body of the UN. Every country that is a member of the UN is represented in the General Assembly. The UN General Assembly convenes annually to deliberate and vote on important issues affecting world peace and security. The General Assembly can only make recommendations to member-states; it cannot make binding decisions, nor can it enforce those decisions – only the Security Council has the authority to do that.
The Security Council is composed of five permanent members—the United States, Great Britain, France, Russia, and China— which were the five main Allied powers in the Second World War. There are also ten non-permanent seats on the Security Council that rotate between different countries every two years. The purpose of the Security Council is to peacefully resolve international conflicts and prevent the outbreak of war. UN Security Council resolutions are binding and are enforced by UN peacekeepers, which are military forces contributed by member-states.
The Economic and Social Council (ECOSOC) was created to promote international economic and social cooperation and development, particularly in the developing world, or what was referred to during the Cold War as the “Third World.”
Finally, the International Court of Justice (ICJ) is the judicial organ of the UN. At its headquarters at the Hague, Netherlands, the court hears legal disputes between states and issues opinions on legal matters submitted by members of the General Assembly or other UN agencies.

The United Nations in the Cold War

Because the Soviet Union and the United States both held permanent seats on the UN Security Council, as the Cold War heated up, disunity between the two great powers interfered with the international organization’s basic peacekeeping mission. This was partly due to the dual nature of the UN as a forum for negotiating disputes among states and a platform for influencing international opinion. The Soviet Union and the United States both used the UN as a propaganda platform, to win hearts and minds in the Cold War. Many of the proposals submitted by US and Soviet officials were aimed primarily at criticizing each other, and since each superpower had a veto in the Security Council, disputes could not be resolved unless both Cold War rivals agreed, which was rare. This had the effect of stalling negotiations and prolonging conflict.4

The evolution of the UN

In the 1950s and 1960s, decolonization, or the process by which former colonial territories became independent states, transformed the composition and functioning of the UN. During this time period, dozens of newly independent countries in Africa, Asia, and the Middle East joined the United Nations and sought to redirect the energies of the organization toward easing the transition to independence.5 As a result of the activism of states referred to during the Cold War as the “Third World,” the UN took on additional responsibilities for economic, political, and social development, and the monitoring and enforcement of fundamental human rights.

What do you think?

Why was the United Nations founded? What does the UN Charter tell us about its main goals?
How did the Cold War affect the functioning and purpose of the United Nations?
How did the UN evolve over the course of the twentieth century?

Want to join the conversation?

  • leaf orange style avatar for user Jeff Kelman
    How is it fair to say, that for hundreds upon hundreds of years, the great Imperialist nations, (the USA, UK, Russia, etc.) all carved out territories and nations for themselves around the globe, and then say that no young nations could have their own annexations or sphere of influence? We are witnessing this today in the middle east and in Africa as nations wish to create new territories and build and change their borders, and we say "no, you aren't allowed to do that." That seems a bit hypocritical to me. I understand the grand high moral stance that this notion of peace is based on, but is it predicated on the notion that all of Earth's national borders were to be set in stone forever into infinity from the year 1946 onwards? How was and is this hypocrisy justified coming from the stance of the great powers to any number of small nations in their own growth stages today?

    Additionally, how is seen as fair, and is it even wise, to have permanent members of the "Security Council"? Sure seems like that is bound to cause problems in the long run, and I mean long run i.e. 100, 200, even 500 or 1,000 years. These sorts of organizations cannot possibly account for all the change the Earth will go through in those longer periods of time.
    (39 votes)
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    • aqualine ultimate style avatar for user Chris Downs
      I think part of the reason that the UN has issues with Middle Eastern and African countries trying to build and change their borders isn't the concept of border changes itself (though maps and globes would need to change with each power shift). In my opinion, their reason behind such a strong opposition to border changes is the means by which the parties trying to acquire these additions are doing it. When you look to these border skirmishes, it isn't war, in most cases. It's just plain massacre. Not to mention that the Geneva Convention was just COMPLETELY thrown out the window when countries like Iran and whatnot aimed for these gains. Citizens are being executed, insurrections and rebellions are spreading like rabbits, and thousands of innocents are being killed, kidnapped, raped, and enslaved. That is why the UN is having issues with these budding Imperial nations, and particularly the US, who sees it as enough of an issue to send soldiers over there. A good example of this was the Gulf War, which I am going to assume many of you all know about, but if you don't know, or don't understand the connection, I will link you a Wikipedia page to read through:


      I will sum up my example here: Iraq was trying to annex Kuwait for its oil, and they were doing it by force. This war is a classic(ish) example of the strong protecting the weak, as Kuwait's military is not as developed as that of the United States. The forceful annexation was the issue, rather than the annexation itself. If Kuwait decided to be annexed out of the people's popular vote, I don't think that there would have been an issue, although the popular vote wasn't the case as Iraq just came and stormed their country.
      (18 votes)
  • duskpin ultimate style avatar for user Harkrit Dhillon
    How many countries are in the United Nations Right Now?
    (7 votes)
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  • male robot hal style avatar for user zhiqiangzeng
    Why did the Soviet Union and the USA have permanent seats and not the other countries?
    (7 votes)
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  • duskpin ultimate style avatar for user mohan .muzhikulath
    who designed the united nations emblem?
    (6 votes)
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  • blobby green style avatar for user jb268536
    What is the cod war?
    (4 votes)
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  • blobby green style avatar for user Asad847
    Israel was a new country created after WWII so that the Jewish people could have their own sense of a nation. Despite good intentions with creating Israel, explain why this decision by the United Nations is controversial.
    (4 votes)
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    • piceratops ultimate style avatar for user Hecretary Bird
      The creation of Israel is so controversial because the land that was granted to the Jewish was inhabited by Muslin. Jerusalem, a holy land for three religions, was suddenly under the control of a people that hadn't been there since the Jewish Diaspora. Arab people were concerned that they would lose control of the Holy Land, and controversy and conflict ensued.
      (5 votes)
  • winston default style avatar for user jeffrey.zamora022
    where is the united nation know
    (3 votes)
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  • starky sapling style avatar for user Kaka-Carrot-Cake
    Can countries like drop out of the UN or is it like a permanent membership once you join?
    (3 votes)
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  • blobby green style avatar for user chhuon.menglin
    Fundamentally, the UN was created for the purpose of international peacekeeping of states, resolving conflicts, making peaceful negotiations over territories. In fact, the UN charter tends to tell the world that this organization basically helps resolve territorial conflicts, having no war over land aggrandizement, and building trust for other states on this organization. In an old saying goes" In a cave, there is only only saber-tooth tiger". Herein, the aims of the UN was to make a solution for conflict sated, negotiate over dispute, and create harmony for cosmopolitan areas. Otherwise, the cold war detrimentally affected and spoiled the main purposes of UN in terms of conflicts. Still, there were prolonging conflicts inside peacekeeping house between
    two superpowers, namely the former Soviet Union and the US. Later, the UN evolved in to a powerful organization that pictured a positive view for other former colonial countries such as Asia, Middle-East, and Africa. Admittedly, the US had burden of duties to maintain order and enforce international fundamental human rights. Simply put, the US was so-called " Third world".
    (5 votes)
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  • leafers sapling style avatar for user Slayer
    If there is UN, then why is there NATO? Whats the difference between them?
    (3 votes)
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    • aqualine tree style avatar for user David Alexander
      As an organization, the United Nations welcomes membership by all nations around the world except Taiwan and a few others. The United Nations acts for the security of all nations.

      The North Atlantic Treaty Organization (NATO) is an alliance of nations created to contain the former Soviet Union and its client states. In the wake of the dissolution of the Soviet Union in 1991, the North Atlantic Treaty Organization sought a new mission, becoming involved in the USA's invasion and occupation of Afghanistan and in some aspects of the Syrian Civil War. Now (2022-2023) that the Russian Federation has risen to second-rate power status in its part of the world, NATO has been reinvigorated and has grown.
      (5 votes)