What would you describe as the most significant political changes in the world in the 20th century?

The most significant changes in politics in the 20th century include:

1) The collapse of colonial empires, including the decline of European monarchies (Russia, Germany, Austria-Hungary);

2) The emergence of the USSR and the establishment of the communist regime on the territory of Eurasia;

3) First and Second World Wars;

4) Formation of the UN;

5) Cold War;

6) The emergence of NATO;

7) the collapse of the Soviet Union;

8) The United States took a leading position in world politics as a result of world wars.

9) Wars in the Middle East.