So?
That means that all of the tribes are represented by the term Jew.
No! What that means is that some Israelites from the Northern Kingdom decided they had enough and moved south to be with the Jews who at that time were observing God's laws. This is one of the reasons why: [I Kings 12:31-32] And he made an house of high places, and made priests of the lowest of the people, which were not of the sons of Levi. And Jeroboam ordained a feast in the eighth month, on the fifteenth day of the month, like unto the feast that is in Judah, and he offered upon the altar. So did he in Bethel, sacrificing unto the calves that he had made: and he placed in Bethel the priests of the high places which he had made.
And this is what subsequently happened in the North:[I Kings 14:15-16] For the LORD shall smite Israel, as a reed is shaken in the water, and he shall root up Israel out of this good land, which he gave to their fathers, and shall scatter them beyond the river, because they have made their groves, provoking the LORD to anger. And he shall give Israel up because of the sins of Jeroboam, who did sin, and who made Israel to sin. This is also why most of the Levites ended up in Judah....they had been spread evenly among the twelve tribes.
So....the Benjamites, most of the Levites and some of the folks from all the other tribes became known as Jews. Strong's #3064. Yhuwdiy (yeh-hoo-dee')a Jehudite (i.e. Judaite or Jew), or descendant of Jehudah (i.e. Judah (Jew)
The Israelites who stayed in the north retained that appellation (Israelite)...never being called Jews in scripture. I know some of you just have a burning desire to prove me wrong, but Biblically....you cannot.
[I Kings 12:21-24] And when Rehoboam was come to Jerusalem, he assembled all the house of Judah (Jehudite), with the tribe of Benjamin, an hundred and fourscore thousand chosen men, which were warriors, to fight against the house of Israel, to bring the kingdom again to Rehoboam the son of Solomon. But the word of God came unto Shemaiah the man of God, saying, Speak unto Rehoboam, the son of Solomon, king of Judah, and unto all the house of Judah and Benjamin, and to the remnant of the people, saying, Thus saith the LORD, Ye shall not go up, nor fight against your brethren the children of Israel: return every man to his house; for this thing is from me. They hearkened therefore to the word of the LORD, and returned to depart, according to the word of the LORD. The people in the Northern Kingdom were never called "Jehudites"!