ORIGINS OF A CATASTROPHE: Yugoslavia and Its Destroyers.

By Warren Zimmerman. Times Books. 256 pp. $35

Ever since Yugoslavia fell apart in 1991, there has been much hand-wringing about how the United States and the European Community could have prevented the breakup--or, failing that, stopped the brutal war that led to the "ethnic cleansing" of Bosnian Muslims by a Bosnian Serb military backed by the "Yugoslav" (in name only) government of Slobodan Milosevic. In this fluently written memoir of his four years as U.S. ambassador to Yugoslavia (1989-92), Zimmerman argues that the breakup was inevitable but that the West could have contained the slaughter by the timely application of limited military force. "The failure of the Bush administration to commit American power early in the Bosnia war," he writes, "was our greatest mistake of the entire Yugoslav crisis."

Ending in May 1992, when Zimmerman was recalled by the Bush administration to protest against Serbian aggression in Bosnia, the memoir describes the ambassador's efforts to persuade Milosevic and the Croatian leader Franjo Tudjman to abandon their expansionist policies. He got nowhere. Milosevic, with "habitual mendacity," denied that he was backing the Bosnian Serbs. Tudjman bragged that Serbia and Croatia had every right to carve up Bosnia. And the Bosnian Serb leader Radovan Karadzic (whom Zimmerman likens to Heinrich Himmler) painted the Bosnian Muslims as fundamentalist fanatics crazed with enmity toward the West. Zimmerman recounts the many quarrels between the United States and the European Community over diplomatic policy, judging them finally a waste. "Short of a credible threat of force," he reiterates, "the United States and its allies lacked decisive leverage."

On the question of how Milosevic and Tudjman--two former Communists--could stir up such a witches' brew of ultranationalism, Zimmerman spurns the myth of Yugoslavia as a land of ancient hatreds. There has been no strong evidence of anti-Muslim feeling for several centuries. And though Serbs and Croats massacred each other during World War II, postwar Yugoslavia saw an intermarriage rate--among all groups--of roughly 20 percent. Embers of ultranationalism had long smoldered in Serbia, but to fan them into conflagration took the bellows of state-controlled television. Once Milosevic made the "rational calculation" that ultranationalism was the path to power, the next step was to fill the airwaves with images of mutilated corpses and other horrors, all neatly blamed on the Croatians or Bosnian Muslims. (The same bloody fare was offered on Croatian TV.) As one Yugoslav journalist remarked, "You Americans would become nationalists and racists too if your media were totally in the hands of the Ku Klux Klan."

In Zimmerman's view, Marshal Tito was partly responsible for the rise of ultranationalism, because his long-lived communist regime forbade any democratic venting of ethnic concerns. Yet Zimmerman is also soft on Tito's regime, playing up its economic successes and playing down its brutality. Equally puzzling is Zimmerman's comment that the Slovenes "bear considerable responsibility for the bloodbath that followed their secession"; elsewhere, he implies that Milosevic and Tudjman would have gone on their rampage regardless of what Slovenia did. These are minor distractions, however, in a book that is required reading for anyone concerned about America's future role in the Balkans--and in the larger world.