These Biblically illiterates that think the nation of Israel today no longer has any relevance in God's Plan are following exactly what the devil wants them to think. They don't know their Bible any more than their fanny.
When God split the old kingdom of Israel into two separate kingdoms, He promised He would always leave one tribe at Jerusalem for His servant David's sake, and Jerusalem's sake.
1 Kings 11:31-36
31 And he said to Jeroboam, "Take thee ten pieces: for thus saith the LORD, the God of Israel, Behold, I will rend the kingdom out of the hand of Solomon, and will give ten tribes to thee:
32 (But he shall have one tribe for My servant David's sake, and for Jerusalem's sake, the city which I have chosen out of all the tribes of Israel:)
33 Because that they have forsaken Me, and have worshipped Ashtoreth the goddess of the Zidonians, Chemosh the god of the Moabites, and Milcom the god of the children of Ammon, and have not walked in My ways, to do that which is right in Mine eyes, and to keep My statutes and My judgments, as did David his father.
34 Howbeit I will not take the whole kingdom out of his hand: but I will make him prince all the days of his life for David My servant's sake, whom I chose, because he kept My commandments and My statutes:
35 But I will take the kingdom out of his son's hand, and will give it unto thee, even ten tribes.
36 And unto his son will I give one tribe, that David My servant may have a light alway before Me in Jerusalem, the city which I have chosen Me to put My name there.
KJV
1 Kings 11:39
39 And I will for this afflict the seed of David, but not for ever.
KJV
Today's nation state of Israel in the holy land represents that "one tribe" (Judah) God promised to leave at Jerusalem. There has always been a remnant of the tribe of Judah at Jerusalem, even during the Babylon captivity. They represent the "house of Judah", the stick of "Judah" per the Ezekiel 37 prophecy of the two sticks.
The ten scattered tribes of Israel, which made up the northern kingdom of Israel, which were NOT known as Jews, were scattered among the Gentiles never to return to the holy land, and would be the founders of the western Christian nations. These are called the "house of Israel", and made up the majority of the early Christian Church in the western nations of history, Great Britain being the first Christian nation to accept Jesus Christ on a national scale.
The Ezekiel 37 prophecy reveals when Jesus returns, the "two nations", or the two houses of Israel, will be put back together as ONE NATION back in the holy land. That is what the joining of the two sticks prophecy is about. It is for the future at Christ's 2nd coming.