On 24 August 1941, two months after Germany invaded the Soviet Union, British Prime Minister Winston Churchill delivered a radio broadcast. Describing the barbarity of German police troops, as he called the SS, he said, "We are in the presence of a crime without a name."
Two years later, Raphael Lemkin, a Polish legal scholar in the United States, came up with a name. Lemkin, a Jew, had managed to escape the Polish occupation and had been studying German policies and tactics ever since.
Lemkin had heard Churchill's speech. In his 1943 book, "Axis Rule in Occupied Europe," Lemkin first used the word "genocide" -- a parallel to homicide -- to describe the extermination of large groups of people.
In 1948, the fledgling UN General Assembly adopted an international Convention on the Prevention and Punishment of the Crime of Genocide, which came into force in 1951. That convention defines genocide as "acts committed with intent to destroy, in whole or in part, a national ethnic, racial or religious group," including inflicting conditions calculated to lead to a group's destruction.
After the horrors of the Holocaust were revealed, the mantra of the time became "never again." But it would take four decades, with the creation of the International Criminal Tribunal for the former Yugoslavia in 1994, before the international community would finally come together to prosecute the crime of genocide again.
Why did it take so long, despite atrocities and mass killings in Cambodia, East Timor, and elsewhere?
"I think there is more political will," said Ben Kiernan, director of the Cambodian genocide program at Yale University. "I think one major development -- the first, in fact -- was the Bosnia tribunal. The concept that genocide had occurred again in Europe in the 1990s was a spur to take action against the perpetrators of the Bosnian genocide. And that, of course, opened the door to other cases -- Rwanda immediately following. And then more recently special tribunals have been established of a mixed national and international nature in Sierra Leone, in Kosovo, and in East Timor."
The definition of genocide as stated in the UN convention includes killing members of a group of people; causing serious bodily or mental harm to members of this group; deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part; imposing measures intended to prevent births within the group; and forcibly transferring children of the group to another group.
Kiernan said the law is evolving, now that the convention is finally being implemented and tested in court. He said he believes it is more likely that cases of genocide will be prosecuted today than ever before.
But the original UN convention was adopted more than 50 years ago. Is the definition of genocide still valid? Is that definition still strong enough to stand up in court?
"Well, I would not say that it's more than enough, but it is certainly enough," Kiernan said. "It's certainly the case that many genocidal perpetrators can be prosecuted under the definition of genocide of 1948."
Kiernan noted that recent prosecutions in Yugoslavia and Rwanda have brought certain developments in international law: "For instance, one development that has occurred is the judgment of the international criminal tribunals that rape death camps and other crimes against women can be considered as a form of genocide against a particular group, by singling out women to persecute as a group."
Several former civilian and military leaders, including ex-Yugoslav President Slobodan Milosevic, former Bosnian Serb President Biljana Plavsic, and Rwandan Colonel Theoneste Bagosora, have been accused of genocide. Plavsic pleaded guilty to lesser crimes, while the trials of Milosevic and Bagosora are ongoing.
Kiernan said it is a difficult process: "Genocide is the most heinous crime against humanity. It is a category of crimes against humanity. It's called an aggravated crime against humanity because to prove it you need to prove not only that the actions were taken but that these actions were carried out with a criminal intent to destroy a group in whole or in part as such. And so that makes it very difficult to prove. But it's also true that these acts would be crimes against humanity even if the intent cannot be proven."
As Kiernan pointed out, several international human rights organizations warned about possible genocide occurring in Rwanda more than 10 years ago. Their voices were not heard at that time.
The same thing, he said, might be happening now in Darfur.