I don't understand. You began by discussing the "continuation of the "People of God"" as related to Catholicism. Others have tried to make that argument. However, then somehow you coupled that with semetic ethinicity. Are you saying Catholics are all ethnically semetic?
The phrase "decendants of Abraham" is not a simple term. There are actual genetic descendants of Abraham (Jews) and there are spirtual descendants of Abraham (believing Gentiles).