Do you think Christians are sincere in their support of Israel?

I have heard many times that they talk about some prophecies that the Antichrist will come from somewhere north of Israel, as he is also called the "king of the north". Those Christians believe he will born in either Russia or Turkey, and that a war will break out. Then, many Jews will die in Israel and Jesus will resurrect and first convert Jews, then take Christians to the Kingdom of Heaven. They always talk about some prophecies like this one and tell "see the prophecy is coming true". I think they see Jews only as human sacrifices and Israel as an alter necessary for them to enter the Kingdom of Heaven. Of course, the Christians I talk about are hard core radical ones.