How was World War 1 the first great turning point of 20th century?

1. Emergence of the United States as a Global Power: Before World War I, the United States had largely pursued an isolationist foreign policy. However, the war's devastation and its impact on global affairs pushed the United States to actively participate in international diplomacy and assume a more influential role on the world stage.

2. Collapse of Empires: World War I witnessed the unraveling of several European empires, most notably the Russian, Ottoman, German, and Austro-Hungarian empires. This marked a significant geopolitical shift, leading to decolonization movements, the formation of new nation-states, and redrawing of political boundaries.

3. Russian Revolution and the Spread of Communism: The war triggered the Russian Revolution, which culminated in the overthrow of the Tsarist regime and the establishment of the Soviet Union. The rise of communism as a political ideology had profound implications for international relations, sparking ideological divides and fueling Cold War tensions that would dominate much of the 20th century.

4. Treaty of Versailles and its Consequences: The post-war Treaty of Versailles placed harsh peace terms on Germany, causing significant resentment and political instability in the nation. It fueled German revanchism and ultimately contributed to the rise of Nazism and the outbreak of World War II.

5. Technological Advancement: World War I witnessed the widespread use of new technologies in warfare, such as machine guns, tanks, aircraft, and poisonous gases. These technological advancements profoundly changed the nature of armed conflict and warfare tactics, reshaping military strategies and capabilities.

6. Social and Cultural Transformations: The war had transformative effects on societies, including the changing roles of women, advancements in women's rights, increased urbanization, and shifts in artistic and cultural movements. The post-war years saw widespread artistic experimentation, avant-garde movements, and a new era of cultural and intellectual expression.

7. Rise of Nationalist and Populist Movements: The aftermath of the war also led to the rise of nationalist and populist movements across Europe, often capitalizing on social and economic grievances and exploiting fears of social decay. These movements laid the groundwork for the totalitarian regimes of the interwar period and helped pave the way for World War II.

Overall, World War I proved to be a watershed moment that dramatically altered the global geopolitical landscape, ushered in revolutionary political changes, advanced technological warfare, spurred societal transformations, and planted the seeds for future conflicts and global uncertainties throughout the 20th century.