I'm glad you presented this. People who do not read the entire Bible and attempt to reconcile ALL that it says, make the error of confusing modern day Israel with the Israel of God.
That was the point of Romans 9,10, 11 and Pauls comments to the Galatians.
And these are all excellent sources to understand just who the Israel of God is. And it is nothting new. It is who it has always been: every believer, either looking forward to Jesus Christ (the Messiah), or those of us who look back.
Here are some of the most telling verses:
Not as though the word of God hath taken none effect, For they are not all Israel, which are of Israel. Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called. That is, They which are the children of the flesh, these are not the children of God, but the children of the promise are counted for the seed. (Romans 9:6-8)
Galatians really is the heart of this doctrine:
Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ. (Galatians 3:16)
For ye all are the children of God by faith in Christ Jesus. For as many of you as have been baptized into Christ have put on Christ. There is neither Jew nor Greek, there is neither male nor female: for ye are all one in Christ Jesus. And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise. (Galatians 3:26-29).
Some may say, this only applies to the NT 'church'. Nonsense. Every faithful son of Abraham will come to Jesus Christ (John 6:37). And Jesus (and John the Baptist) rebuked those who thought by being physical seed that that was sufficient (John 8:39-47, Matthew 3:7-10)). The Bible makes it very clear who these Christ-denying Jews really are:
Who is a liar but he that deneith the Jesus is the Christ? He is antichrist, that deneith the Father and the Son. Whosoever denieth the Son, the same hath not the Father: but he that acknowledgeth the Son hath the Father also. (1 John 2:22,23)
The only hope today for anyone (Jew or Gentile) is to come to Jesus Christ. All have sinned and come short of the glory of God. God is not a respecter of persons. Only the man of faith can please him.
For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God. (Romans 2:28,29)
Radical (basic). And true.
As Jesus said, the kingdom was taken away from the nation of Israel and given to a nation producing its fruits.