What countries were bound to each other by with alliance?

Countries are often bound by alliances for mutual defense, economic cooperation, or political support. Notable historical alliances include NATO (North Atlantic Treaty Organization), which includes the United States, Canada, and many European nations, and the Warsaw Pact, which included the Soviet Union and Eastern Bloc countries during the Cold War. Other examples include the European Union, fostering economic and political integration among its member states, and various bilateral defense treaties, such as the U.S.-Japan Security Alliance. Alliances can shift over time based on geopolitical interests and conflicts.