This is only my opinion but of course, being my opinion it has to be right. Israel sold their birthright and is now only a chosen people. If they come under the Throne of David. There is no kingly line, people, or land outside of the Throne of David. This is because of the treason they committed against God. The promise of their descendants inheriting the land is gone.
The Jews know what it means to sell a birthright with Jacob and Esau.
Birthright
In Genesis, Esau returned to his brother, Jacob, being famished from the fields. He begged his twin brother to give him some "red pottage" (paralleling his nickname, Hebrew: אדום, adom, meaning "red"). Jacob offered to give Esau a bowl of stew in exchange for his birthright (the right to be recognized as firstborn) and Esau agreed.[6]
The birthright (bekorah) has to do with both position and inheritance. By birthright, the firstborn son inherited the leadership of the family and the judicial authority of his father. Deuteronomy 21:17 states that he was also entitled to a double portion of the paternal inheritance.[7]
In the interpretation of Daniel J. Elazar, Esau acts impulsively: "Esau demonstrates that he does not deserve to be the one who continues Abraham's responsibilities and rewards under God's covenant,
https://en.wikipedia.org/wiki/Jacob_and_Esau
We all generally understand the concept if the King or Queen is not dead you do not have a coronation for somebody else to pronounce them as ruler. Such a thing would be considered treason with the harshest of consequences. So what did Israel do?
Israel asks Samuel for a king.
NIV 1 Samuel 8:5 They said to him, “You are old, and your sons do not follow your ways; now appoint a king to lead us, such as the other nations have.
NIV 1 Samuel 8:7 And the LORD told him: “Listen to all that the people are saying to you; it is not you they have rejected, but they have rejected me as their king.
KJV version And the Lord said unto Samuel, Hearken unto the voice of the people in all that they say unto thee: for they have not rejected thee, but they have rejected me, that I should not reign over them.
Now we need to back up for a second. Samuel was a prophet but as a child, he was dedicated to the priesthood or promised to the Lord by his mother. This treason is about to come through the priesthood and prophets. Samuel was not happy about it. So God lets Samuel off the hook when he tells him to listen to the people. Now this is when things should have gotten scary for Israel because God is about to warn them what it means.
1 Samuel 8:9-20 KJV
9 Now therefore hearken unto their voice: howbeit yet protest solemnly unto them, and shew them the manner of the king that shall reign over them.
10 And Samuel told all the words of the Lord unto the people that asked of him a king.
11 And he said, This will be the manner of the king that shall reign over you: He will take your sons, and appoint them for himself, for his chariots, and to be his horsemen; and some shall run before his chariots.
12 And he will appoint him captains over thousands, and captains over fifties; and will set them to ear his ground, and to reap his harvest, and to make his instruments of war, and instruments of his chariots.
13 And he will take your daughters to be confectionaries, and to be cooks, and to be bakers.
14 And he will take your fields, and your vineyards, and your oliveyards, even the best of them, and give them to his servants.
15 And he will take the tenth of your seed, and of your vineyards, and give to his officers, and to his servants.
16 And he will take your menservants, and your maidservants, and your goodliest young men, and your asses, and put them to his work.
17 He will take the tenth of your sheep: and ye shall be his servants.
18 And ye shall cry out in that day because of your king which ye shall have chosen you; and the Lord will not hear you in that day.
19 Nevertheless the people refused to obey the voice of Samuel; and they said, Nay; but we will have a king over us;
20 That we also may be like all the nations; and that our king may judge us, and go out before us, and fight our battles.
Land gone, birthright sold. verse 14 And he will take your fields, and your vineyards, and your oliveyards, even the best of them, and give them to his servants.
They have become slaves, birthright sold. verse 13 And he will take your daughters to be confectionaries, and to be cooks, and to be bakers.
They have become slaves, birthright sold. verse 16 And he will take your menservants, and your maidservants, and your goodliest young men, and your asses, and put them to his work.
The first round of treason and Saul is selected and anointed as king by Samuel, So Israel just used Samuel to commit treason, God’s turn 1 Samuel 10-11 Then the word of the Lord came to Samuel: “I regret that I have made Saul king because he has turned away from me and has not carried out my instructions.” Samuel was angry, and he cried out to the Lord all that night.
You can also think of it in terms of God just rejecting Israel cause they turned away and did not follow his instructions. Kings can represent the nation and they were warned they might become slaves.
1 Samuel 16 1-2 The Lord said to Samuel, “How long will you mourn for Saul, since I have rejected him as king over Israel? Fill your horn with oil and be on your way; I am sending you to Jesse of Bethlehem. I have chosen one of his sons to be king.” But Samuel said, “How can I go? If Saul hears about it, he will kill me.”
The stakes are high with Saul being the current king. We have the same type of pattern as above. God has rejected the King of Israel and can/will claim for his rights what he wants.
The question is, was this issue dealt with when God told Samuel to go and anoint David and that is the end of the matter? I don’t think so, for reasons of the priesthood, and a prophet was used for this treason. The zeal of Aron was replaced by the zeal for a king like the other nations. So my short answer would be just as God replaced Saul with David, He has also in a way replaced the priesthood and the rights of Israel. There is a fork in the road and Israel picked a side. Consider in the King James Version the Book of Psalms 110:4 names Melchizedek as representative of the priestly line through which a future king of Israel’s Davidic line was ordained.
Psalm 110:4 The Lord has sworn and will not change his mind: “You are a priest forever, in the order of Melchizedek.”.
Israel's birthright has been sold. So will God still listen to you and fight for you? That's up to God but there are always other verses in the bible you can try to claim. I did say it was just my opinion.
1 Samuel 8:18-20
18 And ye shall cry out in that day because of your king which ye shall have chosen you; and the Lord will not hear you in that day.
19 Nevertheless the people refused to obey the voice of Samuel; and they said, Nay; but we will have a king over us;
20 That we also may be like all the nations; and that our king may judge us, and go out before us, and fight our battles.
Romans 11:7-10 (WEB)
7 What then? That which Israel seeks for, that he didn’t obtain, but the chosen ones obtained it, and the rest were hardened. 8 According as it is written, “God gave them a spirit of stupor, eyes that they should not see, and ears that they should not hear, to this very day.”
9 David says,
“Let their table be made a snare, a trap,
a stumbling block, and a retribution to them.
10 Let their eyes be darkened, that they may not see.
Always keep their backs bent.”