It is important to remember that at present the European Union is not a federation (like the United States of America), nor is it just an international organisation like the United Nations (UN) where governments merely cooperate together. The EU’s member states remain separate independent states that have ‘pooled sovereignty’ in certain policy areas. This is to say that they have decided to work collectively on particular matters.
These decisions to ‘pool sovereignty’ manifest themselves in the various treaties that have been signed since the creation of the first precursor to the EU, the European Coal and Steel Community in 1951. We will look at the treaties in much more detail in module five but it suffices to say here that each successive treaty has given more responsibility and more sovereignty to the European institutions, culminating in the most recent treaty, the Lisbon Treaty (initially known as the Reform Treaty).
The institutions of the EU make decisions about and administer these decisions on behalf of the member states. However the EU can only make law on a policy area where it has been given responsibility to do so in the treaties. There are some areas of policy (such as tax or defence) where member states retain (almost) full sovereignty and the EU as a whole plays only a minimal role in making policy.
To understand these distinctions it helps to be aware of the EU’s decision making procedures and when they apply.