In Isaiah 9:6, the child to be born will be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace.
For to us a child is born, to us a son is given; and the government shall be upon his shoulder, and his name shall be called Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. Isaiah 9:6 ESV
A prince is one who will one day be king, but does not currently hold that position. Why doesn't Isaiah say that Jesus will be the King of Peace?