Quote Originally Posted by PhinPhan1227 View Post
There will of course be isolated exceptions to any rule. But the example of Genghis Khan you are using is almost the exception which proves the rule. You have one person, who through personal insult wanted a whole group wiped out. In Darfur we have a whole group who wants to wipe out another whole group. Not push them out, not take what they have, not conquer them. They want to exterminate them. And no, in ancient times, you generally didn't see a whole group of people trying to exterminate another whole group of people.
That one person in Genghis Khan is just the leader of a group, no different than leaders of other groups. Many books will equally say it was the Mongols that went on a campaign of extermination in Khwarezm.

The question is was is more or less likely that warring parties would initiate such extermination campaigns in the 20th/21st century or in the 12th/13th (or any other period, say of length 100 years)?

That question I can't answer, but I can tell you I would be surprised if we are more likely to see such campaigns today than in the past. Since you have argued it was different in the past, do you have any stats to back that up? I'll do some googling later on this. It IS an interesting question no doubt.