Which international organization was created to promote peace after World War II?

The creation of the United Nations was a key response to the devastation and conflict of World War II, with the primary goal of fostering international cooperation and promoting peace among nations. Established in 1945, the United Nations aimed to provide a platform where countries could discuss their disputes and work collaboratively to prevent future conflicts.

The UN's foundational principles include the maintenance of international peace and security, protection of human rights, and fostering social and economic development. Its establishment marked a significant effort to create a structured approach to global governance, where countries could engage in dialogue and collective action for the common good, thereby reflecting the international community's desire to avoid the kind of widespread war that had led to such catastrophic consequences during the 1940s.

In contrast, NATO was formed primarily for military defense among member countries; the European Union focuses on economic and political integration within Europe; and the World Trade Organization is centered on regulating international trade rather than promoting peace directly. While all these organizations play important roles in the international arena, the specific mandate of the United Nations centers around maintaining peace and security, making it the correct answer to the question.