The war that started in 1993 between the Muslims and Croats in the southwestern Bosnian town of Mostar had finally stopped. With joint Muslim-Croat police patrols and inter-ethnic trade, the rivals had begun to bridge the divide between them - a divide symbolized by the icy, blue-green river flowing between the mountainous city's Muslim and Croat areas.
The European Union even organized elections June 30 to set up a multiethnic government. But then the society-building went awry. Croats narrowly lost the election and cried foul. Despite much diplomatic wrangling, the EU and US have been unable to persuade Croats to accept the election results and join Mostar's city council.
Frustrated, the EU plans to pull out, and Mostar faces a vacuum of civil authority that NATO peacekeepers are being asked to fill. US officials worry that a similar breakdown over September's nationwide Bosnian elections could unravel peace and require NATO - and its 18,000 US troops - to extend its Bosnia mission.
In 1994, a US-brokered peace agreement brought the European Union to administer Mostar as a demilitarized city.
But after Sunday night's EU-imposed deadline for Croats to join the city council passed with no agreement, EU officials called an emergency meeting in Brussels yesterday. There they discussed the timetable for withdrawal from Mostar. And the NATO-led peace implementation force (IFOR) stepped up patrols in the troubled city, in anticipation of the EU pullout.
"The implications are very serious indeed - especially for the citizens of Mostar. I am very worried about the city becoming totally divided again, about the reunited police force splitting again, about aspects of the freedom of movement and the former confrontation line," says Sir Marton Garrod, the EU chief of staff in Mostar.
Mostar's Croats are demanding a new vote, even though a EU elections ombudsman declared the elections legitimate because the number of votes in question was too low to have affected the poll's outcome.
"There is no room for compromise on such a fundamental issue. The clock is now ticking towards the gradual European Union withdrawal," says EU High Representative for Bosnia Carl Bildt, rejecting Croat demands for a new poll.
Croat refusal to participate in the newly elected city council has thrown into jeopardy the future of the Muslim-Croat Bosnian Federation - the mechanism set up by the accords negotiated in Dayton, Ohio, last year to bring peace to war-torn Bosnia.
"There are implications for the Federation, and extremely serious implications for the September elections, for the Dayton peace accord and the peace process in Bosnia," says Sir Garrod.
The US has pushed for nationwide Bosnia elections to go forward in September, arguing that they are needed to establish a postwar government that can carry on the peace process, and allow NATO to begin withdrawing its 60,000 troops.
"We are greatly disappointed that the local Bosnian Croat leadership in Mostar rejected the EU compromise for establishing a Mostar city government," says White House spokeswoman Kathy McKiernan.
US officials had earlier announced that a Mostar agreement had been reached, following talks between President Clinton and Croatian President Franjo Tudjman in Washington on Friday.
The US is hoping that Mr. Tudjman's desire to join international institutions like the EU and the International Monetary Fund gives Washington some leverage over Tudjman, who enjoys considerable influence over Bosnia's Croats and may be able to persuade them to join the council.
A compromise seemed close on Sunday, but ultimately to no avail.
"We couldn't have gone much further without falling over completely. That agreement was fully accepted by the Muslims. But I am afraid we never got really close to an agreement with the Croats," says Garrod.
International observers in Bosnia have voiced concerns that the peace obtained by NATO troops in Bosnia is largely superficial, and masks - but does not heal - serious rifts still dividing Bosnia's former warring parties.
"The situation in Mostar suggests that Dayton could prove a military success and a political failure. But the military success will erode if we can't establish political stability in Bosnia," says a Sarajevo-based US political analyst.
Another American observer in Sarajevo says Mostar is now an "administrative no man's land. There is no clear line of jurisdiction - no one has ultimate control of the city. There are two mayors, two police forces, two Mafias, and no real government."
But IFOR is playing down its peacekeeping role in the town. "IFOR will provide backup support to the international police, but we are not policemen," says Major Tom Moyer, a NATO spokesman in Bosnia.
With peace, most of Mostar's Muslims want the city to be ethnically reunified, while the city's Croats want to remain separate, or join neighboring Croatia
"There are people who tell me they lie in bed at night, waiting for someone to smash at their door and tell them to get out," says Garrod. The people who would do that have to be cleared out," he says, "otherwise people will never live a peaceful, democratic life."