Treaty of Lisbon

Treaty of Rome

Treaty of Maastricht

Treaty of Nice

Promote protectionism and isolationism

Facilitate trade and investment between EU member states

Restrict movement of goods and services within the EU

Impose trade barriers among EU member states

Create the European Union's customs union

Establish the single market of the European Union

Enhance the democratic legitimacy and efficiency of EU institutions

Formulate the Common Agricultural Policy (CAP)

Establishing a common currency for the Schengen countries

Harmonizing tax policies among EU member states

Regulating agricultural subsidies within the EU

Abolishing border controls among participating countries

Treaty of Lisbon

Treaty of Rome

Treaty of Maastricht

Treaty of Nice

The national level, unless there are clear benefits to EU-level action

The regional level within member states

The local level by municipal authorities

The supranational level by EU institutions

Negotiating trade agreements with non-EU countries

Enforcing EU regulations

Representing the citizens of the EU and legislating on their behalf

Appointing the President of the European Commission

Implementation of common visa and border control policies

Adoption of the euro as its currency

Compliance with common agricultural policies

Formation of a military alliance with other Schengen members

Centralization of political power at the EU level

Formation of a European federal state

Abolition of national governments within the EU

Cooperation and coordination of policies among member states

Erecting trade barriers to protect domestic industries

Restricting imports to safeguard local markets

Promoting free and fair trade with global partners

Subsidizing exports to gain a competitive advantage