1910s: Unrest grows in Tsarist Russia as the oppressive state cracks down on reformers and activists.

1920s: The Bolshevik revolution has taken place, and Lenin is in power. His New Economic Policy is being instituted, which allows greater economic freedom and a measure of controlled capitalism.

Today: Communist Soviet Union has collapsed, and Russia is in ruins following a disastrous attempt to switch to a U.S.-style free market economy.

1910s: After World War I the 1919 Treaty of Versailles establishes an international body that will arbitrate disputes. It also demands that Germany pay reparations for the war.

1920s: The League of Nations has been formed, but its powers are very limited. America refuses to be involved, and has not ratified the Treaty of Versailles. The League is powerless, and fails to prevent the events that lead to World War II.

Today: The United...