There is razor wire fence on the border between Slovenia and Croatia, the only two former Yugoslav republics that have managed to formally enter the fold of the EU so far. The barrier is meant to keep out the hundreds of thousands of refugees still streaming across the “Balkan route” and seeking asylum in the core of Europe. Despite months of increasingly draconian counter-measures, the flow of humanity has continued, virtually unabated. But Slovenia’s barrier is not merely an obstacle for the refugees. It is also a boundary dividing the (relatively) stable democratic regimes of the continent’s west from the apparently unraveling parliamentary democracies of south-eastern Europe.  

One need only glance at a map and have a cursory understanding of events in the region to realise that from Zagreb to Ankara there is nary a stable democratic regime in the whole of south-eastern Europe. Yet few inside of the Brussels establishment—or Washington for that matter—appear to understand how significant the danger is for continental security if the lands between the Adriatic and the Black Sea descend into strife once more.

To be clear, the likelihood of violent conflict in the region akin to the wars of Yugoslav succession is minimal. But for the EU, the threat of its south-eastern underbelly, dominated by weak (and weakening) states, racked by crime and corruption, and sliding towards authoritarianism, is no less perilous.

Take Macedonia, for instance. Though Skopje has been an EU candidate state since 2005, the country has yet to formally begin negotiations with Brussels on membership and in the meantime the country’s nascent democratic regime has all but dissolved. A year-long political crisis recently culminated in the Prime Minister’s resignation, and official mediation on the part of the EU and US, after it was revealed that Nikola Gruevski’s government was illegally wiretapping thousands of political opponents, journalists, academics, activists, and private citizens. In the subsequent crisis management process, headed up by the EU and US, a special prosecutor was appointed to investigate the claims, and snap elections were called. But the prosecutor has been systematically obstructed by the ruling party’s apparatchiks, while thesnap polls have already been delayed.

Meanwhile, in Kosovo, the impasse between the government and the opposition has dissolved into a complete circus and tear gas has become a regular feature of legislative sessions in Prishtina.The opposition has now set up a protest camp outside the Kosovo parliament, in a move that is meant to definitively mark a shift towards the politics of the street and a shift away from legislative processes.

In the rest of the former Yugoslavia, matters are little better. Bosnia-Herzegovina has submitted an application for EU candidate status but this largely spurious gesturebarely obscures the fact that the country is nowhere near the position it needs to stand a chance of acceptance—and won’t be for a decade or more. Croatia is in the midst of its worst post-war constitutional crisis to date, with a hobbled faux-technocratic government presiding over growing cleavages between the country’s dominant political blocs. And while the story in Serbia, according to the Western press, appears to be Prime Minister Vučić’s delicate juggling act between Brussels and Moscow (which has won derision from both in equal measure), the real concern should be with his methodical, and increasingly autocratic seizure of power.

In other EU member states such as Romania or Bulgaria things are hardly much better. Systemic corruption, government instability, and mass protests are the defining features of politics in both countries and have been for years. The Brussels establishment takes naïve solace in the belief that this persistent pattern of democratic deterioration can continue without consequence, indeed, as they did with Macedonia up until last year.

Even at the region’s farthest reaches, there is ample cause for alarm. Hungary’s far-right government has emerged as the leader of an intra-EU illiberal bloc, while Greece still wobbles under the strain of austerity, struggling to cope with the massive waves of refugees making landfall along its coastline. And Turkey is sinking ever deeper into the maelstrom of war—inside and outside of its borders—as President Erdoğan further tightens his grip on what little remains of Turkish democracy.

Increasingly, it appears that what is dividing western European capitals from the chaos in Syria, Iraq, and Afghanistan is a string of weak and failing democratic regimes. We already know that some of the arms used in the November 2015 attacks on Paris came from south-eastern Europe, even if the motivation for the attacks themselves came from further east. But if Brussels, and the core member states of the EU allow much further deterioration of the political and security picture in south-eastern Europe, the fallout will be even more severe.

If the EU – the most prosperous economic union in the world – is struggling to cope with the influx of Middle Eastern refugees, how will it cope with a constellation of de factomafia states and authoritarian regimes just south of the Danube? Especially if Moscow steps up its existing, though so far relatively mild, policy of edging the whole region ever closer to the brink of chaos. Any realistic answer that presumes continued neglect of the region by the EU and US can hardly be cynical enough.

Previously thought an unimaginable trope of dystopian science fiction, the EU as a whole may dissolve depending on the results and fallout of the “Brexit” referendum in the UK. If the institutional framework of the EU collapses, however, and with it, the once fabled “transformative” potential of the Union, the initial pain of this failure will primarily be felt in the polities of south-eastern Europe. But it will not take long for the results to be felt in Berlin and London too.

Lost amid the crisis is the comparatively slower but no less disturbing trend of economic exodus from Kosovo, Macedonia, and Bosnia-Herzegovina. It is no longer war these Balkan migrants are fleeing but years of political brinkmanship, economic stagnation and depression, widespread criminality, and persistent social atrophy. Birth rates are in steep decline across the region, and everyone aspiring for any kind of meaningful future for themselves and their children is leaving now.

Unless both Brussels and Washington renew their political and economic commitment to the region, they may soon find that amid their struggle to resolve the bloodletting in Syria they have lost sight of the growing crisis in south-eastern Europe. And in the coming bedlam, it will be extremists in both Moscow and Raqqa that will seize the day.