The Age That Is Golden

Let us muse today from Zechariah 9:10 and the theme of the coming of the King. He has gone from Christ’s first coming to our text today when Christ will reign in the age that is golden. Our text says He will speak peace and have dominion  over everyone and everything from the sea to the ends of the year. I cannot see how this has ever happened before, it has to be a literal earthly reign that is yet future. It cannot just be symbolized away.