The key here is "in the past" and it is a long ago past and it is not part of Christian Belief. It is nowhere in the Gospels and the OT "genocide" was limited to specified groups in a specified location. With Islam the genocide is in the Koran. It is universal for non-Mohammedans and it is in practice now as it was in the 7th-17th centuries.
You are correct, in the distant past. However, in the present, most evangelicals are still hoping to convert the jews from their "lost " way, and save them! Their basic support for Israel is hinged on the fact that it will bring Jesus back, and will enable them to convert all the Jews to Christianity.