Most Christian Arabs are as fiercely anti-Israel as the Muslims, either in order to survive, or maybe it’s an Arab thing to hate Jews regardless of belief. As noted, this is the safest form of public expression in the region.
The founder of PFLP-GC, one of the worst early terrorist groups was a Christian doctor, George Habash.
Look up the growing phenomenon of “Chrislam” in the ME.
Pali spokespeople like “Arab girl” and Dr. Hanan Ashwari, since they are non-Muslim, can appear on TV in normal attire & be less offputting to us “infidels” in the West.
Again, it’s partly a survival thing.
Or it’s a reminder that American evangelical Christianity is somewhat unusual in that it’s relatively free of the vicious Jew-hate that has characterized the more eastern varieties of Christianity.