United Nations peace-keepers and successive mediators in the Yugoslav wars have found their task bedevilled by confusing lines of authority and a proliferation of power factions.
By contrast, the Bosnian Serbs and the government of Serbia itself consistently display great skill in the exploitation of these political and administrative divisions. The latest crisis is no exception to the rule.
On 22 May Bosnian Serb combatants seized heavy weapons from a UN depot near Sarajevo and one day later their forces began firing on the city. Bosnian government forces fired back.
Lieutenant-General Rupert Smith, the British commander of UN forces in Bosnia, reported the flareup to his superiors based in Zagreb, Croatia - the French General Bernard Janvier and the UN special representative in former Yugoslavia, Yasushi Akashi.
They in turn referred to New York, where the UN Secretary-General, Boutros Boutros-Ghali, was under pressure from the United States to authorise a tough line against the Bosnian Serbs.
Mr Boutros-Ghali and the UN peace-keeping chief, Kofi Annan, took the measure of Russian, French and British opinions in the Security Council and found a formula to satisfy all their requirements. Between New York, Zagreb and Sarajevo a tortuous compromise emerged.
On 24 May, as a result, General Smith gave an ultimatum to both the Bosnian Serbs and the Muslim-led government to cease firing heavy weapons by noon on 25 May. He also ordered the Bosnian Serbs to return the seized weapons within the same deadline and to remove all heavy artillery from a 20km "exclusion zone" by noon last Friday, 26 May.
The UN then had to liaise with Nato's southern command in Naples, which is under American officers, to put ground attack aircraft in Italy on standby for retaliatory air-strikes.
But - crucially - no orders to withdraw were issued from the UN in Sarajevo or Zagreb to vulnerable personnel in Bosnian Serb areas. Yet UN officers knew that more than 400 peacekeepers had been detained last November after air-strikes on a Serb airfield.
The Serbs complied with a ceasefire by noon on 25 May but did not return the heavy weapons. They were attacked from the air during the afternoon. That evening, Bosnian Serb gunners killed 71 people, most of them civilians, in the "safe area" of Tuzla. The first UN hostages were taken.
The next day the UN and Nato seemed to forget about their second noon deadline to clear the exclusion zone. Another attack was launched from Italy against Bosnian Serb bunkers. The Serb response was to shell Sarajevo and to seize more hostages.
The second sequence of air attacks puzzles some diplomats. It seems there was no attempt to change the orders relayed between Sarajevo, Zagreb, New York, Nato HQ in Brussels and Naples. But the French Prime Minister, Alain Juppe, has criticised the actions as "poorly planned". The Ukrainian President, Leonid Kuchma, has said he opposed the air strikes. Russia said it was not consulted about the raids. The Western allies dispute this.
On the Serb side, however, General Ratko Mladic needed only to issue a simple and brutal set of orders.
Now the consequences of this military imbroglio have been dumped back in ministerial laps. The result is to deepen confusion among the estimated 37 nations involved in the Yugoslav morass.
First of all there is the alphabet soup of the UN and its agencies involved in peace-keeping and supplying aid. For air support the UN turns to the Nato chain of command - which excludes France.
The UN has a full-time negotiator, Thorvald Stoltenberg. He works with the European Union mediator, Lord Owen, in the International Conference on Former Yugoslavia. Its deliberations have since devolved on the "Contact Group" of the US, Russia, Britain, France and Germany. The group's ranks are divided. Both the Americans and the Russians have been accused of undermining diplomacy by pandering to Muslim and Serbian interests.
The Western European Union co-ordinates the Adriatic Sea blockade - from which the Americans have partially withdrawn. There is also an "Islamic Contact Group" of Muslim nations supporting the Bosnian government.
The last great Balkan crisis of this kind took place in the 1870s, when Bismarck, referring to its protagonists, grumbled: "One must give these sheep stealers plainly to understand that the European governments have no need to harness themselves to their lusts and rivalries." Today's foreign ministers must privately wish they had heeded the Iron Chancellor's view.