How did World War I, World War II, and the Great Depression change the course of world history in the 20th Century?

The three events are cardinal and have shaped the modern world.

The Great Depression is the worst financial and economic crisis of the contemporary world. It started in 1929 and ended with World War Two. Its effects were so terrible and impacted all major economies on a planet scale, the first serious global economic crisis. Lessons? The crash allowed to learn and understand better the functioning of capitalist economies and of certain cycles. It also spurred new academic thinking that advocated a large role for the government in the economy, promoting and managing social welfare. Such new economic theory is Keynesianism. In the USA, it led to a larger federal government´s involvement to design and implement social policies.

WWI was the most terrible conflict in human history until 1939. It undermined the military and economic might of old colonial powers such as Britain and France; Britain ceased to be the world´s superpower. WWI meant the end of an old world order and was the preamble to a new world order that took a definite shape until the end of WWII. It brought a large role for the USA in global affairs, although the country went back to isolationism after the conflict. It also showed us the gigantic destructive power of new weapons based on scientific and technological progress.

The bad peace it brought sowed the seeds of a new war.

WWII is the most terrible and lethal conflict of human history. It arose from the unjust treatment of Germany by the victorious allies of WWI , the social desperation because of the effects of the Great Depression in Europe, and from the rise of totalitarian fascist regimes. WWII meant the ruin of Europe, the loss of its dominating role in world affairs and paved the way for a new world order, the bipolar system of the Cold War with two superpowers that vied for global hegemony: the USA and the USSR.

Explanation:

answer: because they get bored or smth idk

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