What changes have occurred in the political life of Europe?

The author has not set a time limit. You can consider some continuity of organizations. There was the League of Nations. Clever people decided: war is unnecessary. They decided that any dispute between states can be resolved through negotiations. They embodied the concept of “collective security”. This organization wanted a better life for the people. But some countries did not give a damn about the commitments made and unleashed a war. In a way, the UN can be considered a successor. It functions even this second. The goals and objectives are quite similar to the League. The UN, by its own decision, can send peacekeeping troops to places of armed conflicts. This organization exists at the expense of its members and has tremendous influence among developed countries.