The Western Balkans, a sub-region of the wider European borderlands, historically has been a power vacuum filled by larger states or empires. The end of World War I saw the dissolution of the Austro-Hungarian and Ottoman empires, the states that traditionally had dominated the Western Balkans. Serb-dominated Yugoslavia emerged from within the region to dominate the Western Balkans during the 20th century.
Twenty years after the dissolution of Yugoslavia, the states of the Western Balkans - Serbia, Croatia, Slovenia, Bosnia, Montenegro, Macedonia, Albania and Kosovo - are back to the traditional model of being shaped less by internal dynamics and more by external powers: namely, the West, Turkey and Russia. The changing nature of these external powers, particularly the EU and Nato, but also Turkey and Russia, will be the force that drives the Western Balkans.
The critical driving force of geopolitics is the nation, regardless of whether the nation also takes the form of a nationstate. The European borderlands, which encompass Central Europe, Eastern Europe and the Balkan Peninsula, is comprised of smaller, more numerous nations than Western Europe. Unfavourable geography largely explains this.
A lack of access to the sea, numerous internal mountain chains, insufficient natural barriers and proximity to Asian powers define the region. These factors have hampered the formation of powerful states in the region, providing an opportunity for outside powers to dominate the nearly two-dozen smaller states of the European borderlands.
The traditional external powers of the Western Balkans - Austria, Turkey and Russia - are not as active in the region as during their imperial phases, but they still have designs on the region the primary drivers behind the recent victory of Tomislav Nikolic - whose interest in EU accession is unclear - over Boris Tadic in the presidential elections. For its part, the EU is in no rush to admit Serbia given all of its internal economic and political woes.
In the security sphere, Serbia remains the strongest military power within the Western Balkans, but Nato countries like Croatia and Albania, which joined in 2009, surround Belgrade.
Military action initiated by Serbia against its Nato-shielded neighbours is unlikely in the short- to mid-term. The potential for instability and small-scale conflict remains in the region, particularly in Kosovo. But the degree to which these low-level conflicts become more serious depends less on Serbia than it does on the outside powers that have interests in Serbia and elsewhere in the Western Balkans.
Ultimately, the region revolves not around Serbia, but on the push and pull of outside powers. As a borderland, the external is primary. Right now, the main definer of the region is the EU. A decade ago it was Nato. Before then it was the US-Soviet confrontation, and before then it was Austria, Turkey and Russia, and so on.
The Western Balkans is a region that does not mould itself. It is moulded and remoulded on the broadest level, retaining its regional integrity to some extent. The era of Yugoslav primacy was the one period in which the Western Balkans were autonomous. The autonomy was imposed as a neutral zone between the two blocs of the Cold War, but the internal dynamic was shaped by Serbia. After 1991, Serbia was no longer the one to mould the region.
Therefore, as with most of the countries of the European borderlands, the region will be shaped more by external forces than by its internal dynamics. The Western Balkans cannot be seen as a self-enclosed geopolitical sphere, but as a borderland shaped by outside forces.