Actually the Jews (Judah) were only one tribe of the Nation of Israel. Judah had eleven other brothers and when Jacob gave the blessings [Genesis 48:1-14] the tribe of Joseph became two. Later on, after Mount Sinai, the Levites became a priestly portion of each tribe thereby bringing the total tribe count back down to twelve.
The covenant was given to all of the Israelites. There is much confusion in this regard and many prophecies are directed to both Israel and the house of Judah (Jews).....separately and jointly. If you do not make the distinction you may be attempting to place prophecy and future events on the wrong people....in the wrong place....at the wrong time.
Trying to discern your theology here.
Are you saying that only descendants from the single tribe of Judah are "Jews"?