just as the value of a people is something more then total value of its members, the crime of genocide is a greater crime than the murder of an equivalent number of unrelated individuals. If all people were no more than self intereted in their motives then you would be right. But surely we exist as parts of social groups, and it is the murder of a social group that constitutes the special crime of genocide.
ISIS kills 22 in Yemen's Sanaa, Aden; targets both gov't and Houthi rebels (Reuters)
from the article: Peres to Turks: Our stance on Armenian issue hasn't changed