We in the New World have a much different view of 'ancient history' than do the peoples of the Old World. If some foreign government passed a resolution condemning the United States for condoning slavery by its Founding Fathers, we might bristle a bit, but practically no American citizen alive today would take it as a personal affront. Perhaps the fact that so many of us are descended from immigrants who arrived after slavery was abolished helps us separate ourselves from culpability for that status. The Turks don't have that situation.
They sort of do. The government that conducted the pogrom against the Armenians is no more. It was overthrown not so long after the event.
To blame today's Turks for it, is like blaming todays Germans for Hitler's genocide, except that at some signifigent fraction of Hitler era Germans are still alive, while few pre 1920 Turks are likely to be alive).
Besides, most of us are decended from both pre and post slavery immigrants. Few have ancestors who fall in only one or the other category.