I don't get the problem here what she said was the truth, just because Hitler called the Jews a Race, doesn't mean the The Jews are a race of people like blacks. We have the left now harassing Whoopi for telling the truth.
What am I missing here?
What you are missing is that the whole notion of race is socially constructed. (Yes, that notion is misused by the left, in claiming that all manner of objective realities are socially constructed, but there are, in fact, things which are not objective realities, and are, in fact, socially constructed).
In America, the social construction of race has been formulated on the 'one drop rule': if one has any ancestor from Sub-Saharan Africa, one is "Black". In Brazil, the notion of "Black" is determined entirely by skin color and says nothing about ancestry -- so a Dravidian who moved from India to Brazil would be Black, while an albino descendant of slaves imported from Sub-Saharan Africa would not. In Africa there are racial distinctions among different peoples all with very dark skin, and not always based on skin color (cf. the notorious attempted genocide of dark-skinned ectomorphs -- Tutsis -- by dark-skinned endomorphs -- Hutus -- in Rawanda). The Nazi claim that Jews are a "race" has as sound of scientific underpinnings as the "one drop rule", the Brazilian notion of Blackness, or the body-type distinction that sparked the Rawandan genocide. (Just as there are genetic markers of Sub-Saharan ancestry, of high melanin content in the skin, and of body-type, there are genetic markers of Jewish ancestry shared by Ashkenazim and Sephardim alike.) Which genetic distinctions between populations constitute difference of "race" is not a matter of objective fact, but of social convention only.