1920??? missed it by quite a few years sir. When Sarah told Abraham to have a child with her Egyptian slave Hagar, and Ishmael was born. Finally Sarah did conceive and she had Isaac. Then Ishmael began to torment and mock Isaac and Sarah had Abraham banish her and the boy from them. That torment is still going on to this day. This is the real start of the Arab , Israeli problem, the Arabs are still mocking and tormenting the Jews.
The failure to understand this handicaps anyone trying to understand the Middle East today.