It was a harrowing trip. Aboard Zehra Osmanovie’s bus, a drunken Serb soldier swaggered down the aisle shouting, “Who wants to marry me?” He seized a teenage mother, tore the baby out of her arms and dragged her, screaming, down the steps of the bus. Only the intervention of a Serb officer saved her. When Nura Muharamovic, a frail woman with a glass eye, defended her daughter from the sexual advances of a Serb soldier who had boarded the truck carrying her to Tuzla, he grabbed her elderly husband and disappeared with him. Refugees had similar stories of abuse, rape and murder. On the outskirts of Srebrenica, many saw civilian corpses dumped along the road. They passed blackened houses, still smoldering after the Serbs torched them-in some cases, say United Nations officials,while residents hid in them. They saw bodies hanging from trees, apparently men who had tried in vain to flee through the Serb-held forests.

The fall of Srebrenica leaves a particularly deep gash in the wretched history of Bosnia. It was here that a top U.N. commander made a lonely stand two years ago to defend the 60,000 citizens who had been bombed and starved into near oblivion. Srebrenica became the first of six “safe areas”–the Muslim enclaves that would in theory be protected from Serb attack by lightly armed U.N. peacekeepers (map).

But the Serbs demonstrated the failure of that policy last week. The U.N. command knew well in advance of their intentions to attack Srebrenica. In a June 26 report circulated in New York and Western capitals, Gen. Rupert Smith warned of the enclave’s fate. No one decided to reinforce the town. When the Serbs stormed Srebrenica there was little the 450 Dutch soldiers could do, except ask NATO to halt the airstrikes that hadn’t stopped the Serb assault and had only encouraged them to take dozens of U.N. hostages. After they “cleansed” Srebrenica of Muslims, Serb forces moved artillery and tanks south to attack Zepa, ordering its U.N. and Muslim defenders to surrender. “There are only 69 Ukrainians there,” says a senior NATO official. “And half of them are drunk.”

Once again, the hideous images of refugees squeezed the West to do so something. America and its allies didn’t know whether to fight or fold–or continue to muddle through. Renewed calls to withdraw U.N. forces and avoid further humiliation at the hands of the Serbs threw the West into a deep funk. French President Jacques Chirac vowed to call his soldiers home or to retake Srebrenica–provided Britain and the United States agreed to pitch in within 48 hours. The taunt didn’t sit well on Downing Street, where a senior British official fumed about “Gallic rhetoric” over a lost cause. A top Pentagon official called Chirae a “blowhard.” President Clinton saw an opening for a new approach to Bosnia. He and Chirac talked on the phone. But, instead of engaging in a substantive discussion, says a U.S. official, the French president seemed “very explosive . . . talking generally about how horrible the West looked.” Still, Chime shelved his threat to pull out French forces. That temporarily relieved Clinton of his worst foreign-policy nightmare: sending up to 25,000 U.S. troops to aid a U.N. pullout, leading to what a senior administration official calls “the inevitable Americanization of the war.”

But the United States does plan to enter the conflict in a more significant – and perilous-way. The NATO allies will try to halt the Serb rampage at Gorazde, which is well defended, loaded with refugees and the site of a large arms factory. Washington is taking a serious look at airlifting 1,000 French troops into the Muslim enclave. NEWSWEEK has learned that at a principals’ meeting at the White House late last week, Gen. John Shalikashvili, chairman of the Joint Chiefs, presented a plan for a massive air assault at night-the largest helicopter armada since Vietnam. Waves of Black Hawks would carry in the troops, with Apaches as escorts and AC-130s riding shotgun; support aircraft could include F-16s and A-10s. The operation would almost certainly result in U.S. casualties. “These are very dangerous conditions to be flying,” says a senior White House aide. Operational details were to be worked out on Sunday in London, when Shalikashvili met with British and French defense leaders.

Why draw the line at Gorazde? If the Serbs overrun Zepa, Gorazde becomes the sole eastern enclave in Muslim hands. It is also the last significant bargaining chip for the Bosnian government if it ever decides to swap territory for an undivided Sarajevo. U.S. intelligence sources now believe the Serbs are bent on an all-out military victory–including the Bosnian capital. “Sarajevo is the prize,” says a Pentagon source. “But if Gorazde falls and the U.N. pulls out, then Sarajevo is doomed.” So the White House has ordered up plans to break the siege of Sarajevo–to open up a relief route and improve the city’s defenses.

None of this will go down easily in the Republican-controlled Congress. Both Bob Dole and Newt Gingrich have branded U.S. policy a failure, calling for a U.N. pullout and lifting of the arms embargo. “This is the the worst performance by the democracies since the late 1950s,” Gingrich said, echoing candidate Bill Clinton’s critique three years ago. Yet arming the Muslims would require putting U.S. advisers on the ground for months, if not years. That’s something that Clinton–like George Bush before him–has tried to avoid. But the brutal lesson of Bosnia is that half-measures don’t work.

Tuzla Refugees: 223,000 U.N. forces: 1,139 Nordic and Jordanian troops Zepa Refugees: 20,000 U.N. forces: 69 Ukrainian troops Gorazde Refugees: 60,000 U.N. forces: 300 British and Ukrainian troops SOURCE: U.N.H.C.R.