Context, brother, context.
Paul calls the Isreal he is talking about enemies of the gospel. Your statement does not fit that at all.
That's that one verse. Lets not take one verse and make a doctrine out of it.
Concerning who is the true Israel, Paul has written much more. Lets not ignore them.
Romans 9
1 I say the truth in Christ, I lie not, my conscience also bearing me witness in the Holy Ghost,
2 That I have great heaviness and continual sorrow in my heart.
3 For I could wish that myself were accursed from Christ for my brethren, my kinsmen according to the flesh:
4
Who are Israelites; to whom pertaineth the adoption, and the glory, and the covenants, and the giving of the law, and the service of God, and the promises;
5 Whose are the fathers, and of whom as concerning the flesh Christ came, who is over all, God blessed for ever. Amen.
6 Not as though the word of God hath taken none effect.
For they are not all Israel, which are of Israel:
7
Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called.
8
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
....
18 Therefore hath he mercy on whom he will have mercy, and whom he will he hardeneth.
...
24 Even us, whom he hath called, not of the Jews only, but also of the Gentiles?
25 As he saith also in Osee, I will call them my people, which were not my people; and her beloved, which was not beloved.
26 And it shall come to pass, that in the place where it was said unto them, Ye are not my people; there shall they be called the children of the living God.
27 Esaias also crieth concerning Israel,
Though the number of the children of Israel be as the sand of the sea, a remnant shall be saved:
Only a remnant of Israel shalt be saved. And Loruhamah has become Ruhamah and Loammi has become Ammi. This is consistent with the whole of Paul's teaching.
Galatians 3
28 There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus.
29 And if ye be Christ's, then are ye Abraham's seed, and heirs according to the promise.