Replacement theology is a pejorative term and often used as a tool against those who believe in the "New Covenant". Supersessionism is the proper term when speaking of "one" people in Jesus Christ of Nazareth both Jew and Gentile. The danger of twisting scripture once again with this system is that it invites the dual covenant theory that the Jews can live under the Mosaic Law while the rest of us who have been regenerated can live under the New Covenant of Jesus Christ of Nazareth. This, IMO, is the most wicked part of this system. The most prolific proponent of this theory is John Hagee. He believes that just merely being a Jew brings you to salvation and that any attempt to bring the "Good" News" to them is "a waste of time". Very dangerous person.