For many years, especially in the aftermath of the Cold War, the European Union (EU) was a source of inspiration. It inspired other countries around the world to embrace regionalism.
Mark Beeson (2004) argues that regionally based interactions are central components of the international order at the start of the 21st century.
One fundamental reason to pursue regionalism is to enhance economic liberalization. A series of deadlocks in WTO negotiations in the late 1990s motivated nations to think about having more substantially intensive, but more regionally localized, economic blocs.
The EU played a pivotal role in this by successfully constructing a supranational mechanism that integrates economic, social and (to some extent) political supremacies over national existence.
Taking the EU as an example, other regional institutions such as ASEAN, NAFTA, MERCOSUR...