When Cain killed Abel, the Bible recorded it as the first murder in history. But the rabbis commented, this is more than murder. Abel’s murder opened the jaws of genocide. For when Cain killed Abel, it wasn’t Abel alone that died.
Parshat Vayishlach (Genesis 32:4-36:43) Certainly, ours is a history of being targeted by "them" for no reason other than our being "us." The Christian, en route to liberate the Holy Land from the infidel Muslim Saracens, stopped along watering holes throughout Europe to massacre whole Jewish bystander communities.
It began with the first two human born into this world, the world's first brothers.