The member states of the European Union are aligned in their foreign policy on many issues. The EU is the world's largest economic union, customs union and donor of humanitarian and development assistance and thus has an extensive network of delegations around the world mainly operating in the framework of External Relations, for which the European Commission is the main decision body. The EU also represents shared political and security viewpoints held by its member states, as articulated in the Common Foreign and Security Policy.
The EU's predecessor, the European Coal and Steel Community, opened its first mission in London in 1955, after three years non-EU countries began to accredit their missions in Brussels to the Community. The US had been a fervent supporter of the ECSC's efforts from the beginning, and Secretary of State Dean Acheson sent Jean Monnet a dispatch in the name of President Truman confirming full US diplomatic recognition of the ECSC. A US ambassador to the ECSC was accredited soon thereafter, and he headed the second overseas mission to establish diplomatic relations with the Community institutions.
