Rabbi Meir Kahane said in his final shiur at the yeshiva
"...Because there is no time. Who knows how much time is left. We have to say it - and then, 90% of our supporters will leave us. Oh well, so be it. But we have to say it. To say: Do Tsheuva! But not just the tsheuva that everyone else talks about. Of course Shabbat, and of course Kashrut, learning Torah, modesty - everything. But - to wreck the relations! That is the real tsheuva! To cling to God, and to separate ourselves from them. One cannot cling to God without separating himself from them. It doesn't go together. That's it. It's not easy. Isolation was always difficult. It is something that always caused worry. But it has to be. We are a "nation that dwells alone" (Am livadad yishkon - BaMidbar, 23:9). People read the verse. How nice. What a nice song it makes. But it isn't a song, and it isn't some nice saying. It is Jewish law. The laws of isolation."
If you doubt that we are so intwined with Esav that it is hard to tell the difference between a Jew and a Christian watch the following video.
Christian Jews or Jewish christians?