As happened after Cambodia's killing fields and the slaughter of Hutus in Rwanda, the chief perpetrators of "ethnic cleansing" in the former Yugoslavia are emerging unscathed, despite the convening of war crimes trials in The Hague. This is in marked contrast to post World War II trials and convictions of top German and Japanese political and military leaders by tribunals in Nuremberg and Tokyo. PNS commentator Thi Lam, a former general in the South Vietnamese army and now a writer in San Jose, Calif., looks at the lessons to be drawn.

As the first international war crimes trials since the end of World War II convene in The Hague in an effort to bring justice to war-ravaged former Yugoslavia, the striking fact is that the chief perpetrators are nowhere to be found. The message is clear: when the United Nations or Western powers try to intervene in a civil war, war criminals escape unscathed as the price for a brokered peace.

This may be a sign of the times. Political and military leaders in emerging countries can perpetrate genocide and still expect to be home free depending on the eagerness of Western powers to get involved and the tactical situation on the battlefields at the time of negotiations. Thus, when UN Ambassador Madeleine Albright visited Serb-held Croatia last March to press for prosecution of war criminals, she was pelted with insults and stones. The barrage reflected the belief of warring factions that atrocities were to be expected in a civil war and that most perpetrators of war crimes should be left alone. And the United Nations and the Western powers, eager to restore peace and end suffering, were willing to accommodate.

At a recent meeting in Geneva, the presidents of Serbia and Croatia agreed to surrender three suspected war criminals to an international tribunal. But so far, Radovan Karadzic, the president of Bosnian Serbs, and his military commander, Ratko Mladic -- both indicted on charges of genocide by the International Tribunal at The Hague -- remain at large. Indeed, of the 57 war crime suspects indicted by the tribunal, only three so far are in custody.

Similarly, Pol Pot, the Khmer Rouge leader accused of murdering 1.5 to 3 million of his countrymen, has been living comfortably in Thailand where he directed the lucrative timber and gem exploitation in northwestern Cambodia.

When half a million Rwandans were slaughtered by Hutu militiamen in 1994, the United Nations and Western powers not only decided to avoid getting involved but mounted no effort to ensure the prosecution of those responsible for the slaughter. Most of the Hutu leaders were able to escape to neighboring countries after they were defeated by the rival Tutsi ethnic group. Significantly, at a recent meeting in Tunisia convened to solve the Rwanda refugee problem, former U.S. President Carter and the presidents of Rwanda, and neighboring Burundi, Tanzania, Uganda and Zaire remained conspicuously silent on the issue of bringing Rwanda war criminals to justice.

The Geneva conventions of 1949 and The Hague Regulations of 1907 define two types of "war crimes": crimes against peace, which include planning, preparing, initiating, or waging wars of aggression, and crimes against humanity, which include murder, extermination, deportation, torture, and other mass atrocities and persecutions of entire racial, religious and political groups.

By these standards, the Khmer Rouge genocide in Cambodia, the Hutu mass murders in Rwanda and Bosnian Serbs' "ethnic cleansings" all qualify as crimes against humanity.

Yet whereas the war criminals in World War II were put on trial and convicted, the perpetrators of genocide in Cambodia, Rwanda and Bosnia are going free. At the least this reflects a frightening decline in a collective world conscience and the callousness of modern realpolitik. Heinous war crimes are allowed to go unpunished for the sake of political expediency.

There is, of course, another explanation. In World War II, Germany and Japan were defeated, the perpetrators were arrested, and international tribunals were set up by the victorious Allied powers. In the cases of Cambodia and Bosnia, the Khmer Rouge and the Bosnian Serbs did not lose the war and the perpetrators were never apprehended. Although they were expelled from Phnom Penh and other major cities, the Khmer Rouge were able to regroup in western Cambodia where they put up fierce resistance to government troops. At the time of peace negotiations, the Bosnian Serbs occupied more than half of Bosnia and were locked in a seesaw battle with the Muslim-Croat coalition.

"Winners are kings; losers are pirates," goes a Vietnamese proverb. And those who neither win nor lose can get away with their crimes.