Hopes were high at the end of the Second World War that the victorious "great powers" (United States, Britain, France, Russia and China) would be able to ensure world peace through the United Nations Security Council by means of peacekeeping operations and disarmament.
Over the years, the United Nations has come to believe that peace requires that everyone share in the fruits of economic development. To that end they established the World Bank, International Monetary Fund and World Trade Organization, as well as the UN Development Programme and most recently the campaign for the Millennium Development Goals.
Many believe that the most important contribution to peace thus far by the United Nations has come from the General Assembly in its role as a universal place for discussion and dialogue. The Assembly has achieved two great consensus documents, the Universal Declaration of Human Rights (1948) and the Declaration and Programme of Action for a Culture of Peace (1999).
The five "great powers" of the Security Council have used peacekeeping operations to "put out fires" in the lesser countries. But they have held on to their nuclear weapons and resisted disarmament. To discuss this in detail, go to peacekeeping or disarmament
The World Bank, International Monetary Fund and World Trade Organization are controlled by the United States and its allies. They use them to increase their economic power at the expense of the poor countries of the South. To discuss this in detail, click here on the UN and development.