What evidence can you give that the verse is speaking about Israel?
Are there not people who are not Israelites who are "lost"?
"Seeing then that we have such hope, we use great plainness of speech: And not as Moses, which put a veil over his face, that
the children of Israel could not stedfastly look to the end of that which is abolished: But
their minds were blinded: for until this day remaineth the same vail untaken away in the reading of the old testament; which vail is done away in Christ. But even unto this day, when Moses is read, the vail is upon
their heart. Nevertheless when it shall turn to the Lord, the vail shall be taken away. Now the Lord is that Spirit: and where the Spirit of the Lord is, there is liberty. But we all, with open face beholding as in a glass the glory of the Lord, are changed into the same image from glory to glory, even as by the Spirit of the Lord. Therefore seeing we have this ministry, as we have received mercy, we faint not; But have renounced the hidden things of dishonesty, not walking in craftiness, nor handling the word of God deceitfully; but by manifestation of the truth commending ourselves to every man's conscience in the sight of God. But if our gospel be hid, it is hid to them that are lost: In whom the god of this world
hath blinded the minds of them which believe not, lest the light of the glorious gospel of Christ, who is the image of God, should shine unto them." 2 Cor 3:12-4:4
In order to be lost, you must first belong.