From the Summary: "This report provides answers to key questions related to the European Union (EU). It describes the EU's evolution, its governing institutions, trade policy, and efforts to forge common foreign and defense policies. The report also addresses the EU-U.S. and EU-NATO relationships. It will be updated as events warrant. For more information, see CRS [Congressional Research Service] Report RS21344, 'European Union Enlargement', and CRS Issue Brief IB10087, 'U.S.-European Union Trade Relations: Issues and Policy Challenges'."
CRS Report for Congress, RS21372