WAR ON ALL FRONTS

The war in Bosnia flares like a midsummer forest fire, defying the West's wavering attempts to contain it. On Friday, July 21, the NATO allies announced a bold new plan to deter Serb aggression. In the days that followed this call to arms, Ratko Mladic, the commander of the rebel Bosnian Serbs, seized and "ethnically cleansed" one "safe area," Zepa, and intensified a brutal assault on another, Bihac. Meanwhile, an eventuality that the U.N. and NATO had dearly hoped to prevent--a widening of the Balkan war--seemed by Friday to have occurred, as Croatia joined the fighting. Not a very good record for any week, much less one that was supposed to be marked by the West's new determination to halt the slaughter.

On Tuesday Bosnian Serbs finally occupied the eastern enclave of Zepa, which they had been attacking since June, and promptly ejected 5,000 women, children and old men because they were Muslim. The Serbs then looted and set fire to the town. The refugees reached Bosnian government lines exhausted and dazed, but apparently without suffering the sort of atrocities the Serbs had inflicted on the 42,000 residents of Srebrenica two weeks before. (A U.N. commission accused Mladic and Radovan Karadzic of genocide last week.) The New York Times reported Bosnian claims that the Serbs had used some sort of gas attack to rout the last of Zepa's defenders, but details of the assault could not be confirmed.

After Zepa fell, Mladic increased his merciless pressure on Bihac, an isolated U.N. safe area in the northwest. Coordinating efforts with Serb rebels from neighboring Croatia and antigovernment Muslim irregulars, he attacked the so-called Bihac pocket, a cluster of towns and villages that shelters more than 160,000 people, mostly Muslims. He and his allies, totaling about 25,000 men, rolled up a third of the pocket and drew to within two or three miles of the main U.N. camp at Coralici, where 1,300 poorly armed Bangladeshi peacekeepers are holed up.

Those Serb attacks, in turn, triggered a counteroffensive by Croatia, across the border from Bihac. Up to 10,000 Croat troops attacked south and west of Bihac, cutting a main supply route between the two Serb strongholds of Knin in Croatia and Banja Luka in Bosnia. Artillery fire sent 5,000 Serb civilians fleeing from the town of Bosansko Grahovo, which the Croats captured on Friday. Croat forces followed up by taking nearby Glamoc and shelling Strmica. Karadzic confirmed that his army had "withdrawn to reserve positions" and ordered full mobilization in the 70% of Bosnia already in his grasp.

The stirring of Croatia is one of the most important events of the war in years. One-third of the country was seized by rebel Croatian Serbs in 1991. Ever since, President Franjo Tudjman has been preparing openly for a campaign aimed at recapturing that land, and the Croatian armed forces have been rebuilding and training with new weapons. In May they took back Western Slavonia, and it has been assumed that a major Croat offensive would begin this summer. The action last week seemed to be the overture. By week's end, young men had disappeared from the streets of Zagreb, called up into the army, and Croat forces had begun to gather near Karlovac, just north of Krajina. A U.N. spokesman says massive Croat attacks on Krajina, the Serb-held portion of Croatia, "may be initiated soon, possibly within days."