The build-up of tension in Mitrovica is a sharp reminder of the unresolved conflict in Kosovo, after NATO's war against Serbia. 38,000 troops under NATO command are there to keep the peace, including a small contingent of Irish soldiers. But they have not been able to prevent attempts to partition the town of Mitrovica in the northern part of Kosovo. In many respects this is a microcosm of the conflict in Kosovo as a whole. Recent weeks have seen the forced movement of Albanians from the northern part of the town to the south, across the River Ibar. They have been prevented from returning to their homes by well organised crowds of Serbs, who have been joined by Serbs from the southern part of the town.
The tension is suspected of being stoked up by the Yugoslav president, Mr Slobodan Milosevic, in Belgrade. Were Mitrovica to be effectively partitioned, he would have struck a blow against the NATO peace-keeping force and set a precedent for a more long-term plan to exchange Serb and Albanian populations forcibly between southern Serbia and the region around Mitrovica. That would further plans to partition Kosovo against the wishes of the majority of its inhabitants. The reversion of nearby mining resources and religious centres to Serbia would seem to form part of this plan.
There is much at stake in this confrontation. The fact that tens of thousands of Albanians joined a protest march to Mitrovica, many coming from miles away, confirms the depth of feeling involved. It underlines the slow movement being made towards setting up a civil administration - a responsibility given to the special United Nations organisation under Mr Bernard Kouchner.
It is difficult to build confidence and new institutions after such a wrenching conflict, when final political settlement is left as yet unresolved. No one should be surprised that Mr Milosovic should choose to stoke up tension at just such a sensitive moment.
It does not help that little progress has been made in putting the Stability Pact for Regional Reconstruction in place after the Kosovo war last year. It contains political commitments to include the Balkan States in long-term plans for European integration, as a stimulus to develop good neighbourly relations among them.
Ahead of that, there are commitments to finance reconstruction in the region and compensate states for costs and damage incurred in the war. But money has been very slow in coming. States such as Bulgaria and Romania are still suffering severely from the complete disruption of Danube freight traffic caused by bombing bridges during the war. The refusal to lift sanctions against Serbia reinforces the case for compensating these states, but that has not been done either.
This story has all the signs of a sad tale of international tension shifting after the intensity of war. But the post-war regime was put in place in full awareness of the need for long-term involvement. Circumstances do not stand still in that part of Europe, especially as long as Mr Milosovic remains in power. The events in Mitrovica should remind everybody concerned that unless the political and military commitments to Kosovo and the Balkan region are delivered, the progressive vision of an inclusive Europe, articulated after the Kosovo war, will be sadly eroded.