To expand on this a bit, one of the particular passages used for why Christians "must" support the current state masquerading as "Israel" is Genesis 12:2-3, in which God says to Abram, before his name was changed to Abraham:
> "I will make you a great nation; I will bless you And make your name great; And you shall be a blessing. I will bless those who bless you, And I will curse him who curses you; And in you all the families of the earth shall be blessed."
Therefore they see a danger in cursing Israel, since they are presumably Abraham's descendants, who inherit the promises made to him, and those who curse them will themselves be cursed.
This, of course, ignores two important principles:
1. Inclusion in God's covenant with Abraham has ALWAYS been on the basis of sharing the same faith Abraham had, and not by birthright. Consider Ishmael and Esau as pointed out by Paul in Romans 9 and consider Christ's words to the Pharisees and Sadducees in Matthew 3:8-9:
> "Therefore bear fruits worthy of repentance, and do not think to say to yourselves, 'We have Abraham as our father.' For I say to you that God is able to raise up children to Abraham from these stones."
While there is definitely a generational inheritance aspect to the covenant of God, it is NOT an automatic and universal inheritance that disregards faith, and especially since messiah has come, it is not without submission to and faith in Jesus Christ.
2. Those unfaithful who were descended from Abraham by blood were specifically called by Christ "children of your father, the devil" in contrast to their claim of being children of Abraham.
We see this very plainly in Jesus' teaching in John 8. Here he says to "those Jews who believed him" (verse 31):
> "If you abide in My word, you are My disciples indeed. And you shall know the truth, and the truth shall make you free."
Shortly thereafter, in verse 39, some unbelieving Jews answered him saying, “Abraham is our father," as though that should be the end of the matter. What is Jesus answer to this? He tells them they are no children of Abraham, and they prove it by their actions.
> "If you were Abraham's children, you would do the works of Abraham. But now you seek to kill me, a man who has told you the truth which I heard from God. Abraham did not do this."
He goes farther, telling them who their true father is in verse 44:
> "You are of your father the devil, and the desires of your father you want to do."
So, the Jews who reject Christ, like the ones who put him to death, have no rightful claim to be called "children of Abraham," or heirs of the promises made to him. Rather, they are children of the devil, according to Christ himself, whom are later called "the synagogue of Satan" in Revelation 2:9 and 3:9.
True Israel, God's covenant people, is synonymous with the Christian church, firmly holding to the teaching of the Apostles and the Prophets, and none other. The rest are no sons of Abraham whatsoever, but are of their father, the devil.
