Germany's aggression: Germany's territorial ambitions and aggressive actions, such as the invasion of Poland in 1939, prompted other countries to take action to defend themselves and maintain the balance of power in Europe.
Ideological conflicts: The conflict between the fascist ideologies of Germany, Italy, and Japan, and the democratic principles and values of other nations contributed to the ideological dimension of the war.
Economic factors: Control over resources and economic interests also played a role. For instance, the Allied Powers sought to counter Germany's economic dominance and secure access to vital raw materials.
Colonial empires: The competing interests and colonial ambitions of different countries added another layer of complexity, drawing more nations into the conflict.
Global reach: World War 2 was not confined to Europe alone. Japan's expansionist policies in the Asia-Pacific region and the United States' involvement in response created a global theater of war.