EU enlargement: What does the future hold?

To “widen” or to “deepen”. This has been one of the longstanding dilemmas throughout European Union (EU) history, and a perennial sticking point in the unending process of European integration.

In its time, the UK championed a wider EU, while France pushed for a deeper one. The British were heavily invested in the single market, so their preference for indefinitely expanding the number of member states served two purposes: maximizing economic exchange, and making the possibility of EU political federalization as difficult as possible, as more members would make any decision-making process more complex.

Though also interested in an expanded market, France prioritized a focus on supranational political integration as a way to strengthen the EU’s foundations.

Widening and deepening are not mutually exclusive. In fact, both are essential to European integration, and in practice both policies coexist, as all enlargements have brought about changes. The debate is therefore not about choosing one or the other, but rather the impact of prioritizing one or the other on the power balance among EU member states.

All EU expansions involve renegotiating voting rules, as well as a shift in the influence held by different countries in EU institutions. Since its inception, the EU has expanded eastward, and Russia’s attack on Ukraine means this is expected to continue. However, it is unclear exactly where “Europe” ends.

The 2004-2007 EU enlargement

In looking at current candidates for EU accession, it is worth first examining its fifth enlargement, which took place from 2004 to 2007.

Despite various shortcomings, this expansion was broadly successful in making new members more “European” by Western standards.

However, the enlargement was