"There is no historical proof that the famine was organized along ethnic lines," reads an excerpt in the Washington Post from a Russian parliament resolution passed last month. "Its victims were millions of citizens of the Soviet Union, representing different peoples and nationalities living largely in agricultural areas of the country."

But Ukrainian President Viktor Yushchenko claims that, during the famine, Ukraine became "a vast death camp," the Post reports.

"Other parts of the Soviet Union suffered terribly as well," he wrote in a letter last year to the Wall Street Journal. "But in the minds of the Soviet leadership there was a dual purpose in persecuting and starving the Ukrainian peasantry. It was part of a campaign to crush Ukraine's national identity and its desire for self-determination."

This tricky business of categorizing mass death will no doubt come into focus as the Khmer Rouge Tribunal progresses. The term "genocide" was defined under international law in 1948 as a reaction to the Nazi Holocaust. In that year, the United Nations General Assembly adopted the Convention on the Prevention and Punishment of the Crime of Genocide, defining genocide as "the intent to destroy, in whole or part, a national, ethnical, racial or religious group."

Since that time, "genocide" has become much more liberally defined by mass culture. Any horrific campaign of extermination will be called genocide at some point. And, for various reasons, people believe this term carries more weight than "mass murder" or other, less impressive, labels for tragedy.

But when we look at the pure definition of genocide, it becomes clear that many crimes described as such are not, in fact, genocide. Would the murder of ethnic Vietnamese and Cham Muslims by the Khmer Rouge be genocide? Probably. But what about the hundreds of thousands of Cambodians killed for having attended college, or speaking French?

Did the Soviet government single out Ukrainians for particularly brutal starvation, simply because they fought for a national identity? Or was the death toll in Ukraine higher than in other parts of the Soviet Union because it was a largely agricultural area?

When examining tragedy under current international laws, these are important questions. But from a moral perspective, do such distinctions even really matter?

Perhaps it is time to revise the traditional definition of genocide. Or, for the international community to recognize that crimes that don't meet the current term's criteria can be equally horrific.