Good point. I better check the context to see if it is referring to the millennial kingdom:
1Behold, a day is coming for the LORD when the spoil taken from you will be divided among you.
2For I will
gather all the nations against Jerusalem to battle, and the city will be captured, the houses plundered, the women ravished and half of the city exiled, but the rest of the people will not be cut off from the city.
3Then
the LORD will go forth and fight against those nations, as when He fights on a day of battle.
4In that day
His feet will stand on the Mount of Olives, which is in front of Jerusalem on the east; and the Mount of Olives will be split in its middle from east to west by a very large valley, so that half of the mountain will move toward the north and the other half toward the south.
5You will flee by the valley of My mountains, for the valley of the mountains will reach to Azel; yes, you will flee just as you fled before the earthquake in the days of Uzziah king of Judah. Then the LORD, my God, will come,
and all the holy ones with Him!
6In that day there will be no light; the luminaries will dwindle.
7For it will be a unique day which is known to the LORD, neither day nor night, but it will come about that at evening time there will be light.
8And in that
day living waters will flow out of Jerusalem, half of them toward the eastern sea and the other half toward the western sea; it will be in summer as well as in winter.
9And
the LORD will be king over all the earth; in that day the LORD will be
the only one, and
His name the only one.
10All the land will be changed into a plain from Geba to Rimmon south of Jerusalem; but Jerusalem will rise and remain on its site from Benjamin’s Gate as far as the place of the First Gate to the Corner Gate, and from the Tower of Hananel to the king’s wine presses.
11People will live in it,
and there will no longer be a curse, for Jerusalem will dwell in security.
12Now this will be the plague with which the LORD will strike all the peoples who have gone to war against Jerusalem; their flesh will rot while they stand on their feet, and their eyes will rot in their sockets, and their tongue will rot in their mouth.
13It will come about in that day that a great panic from the LORD will fall on them; and they will seize one another’s hand, and the hand of one will be lifted against the hand of another.
14Judah also will fight at Jerusalem;
and the wealth of all the surrounding nations will be gathered, gold and silver and garments in great abundance.
15So also like this plague will be the plague on the horse, the mule, the camel, the donkey and all the cattle that will be in those camps.
16Then it will come about that any who are left of all the nations that went against Jerusalem will go up from year to year
to worship the King, the LORD of hosts, and to celebrate the Feast of Booths.
17And it will be that whichever of the families of the earth does not go up to Jerusalem to
worship the King, the LORD of hosts, there will be no rain on them.
18If the family of Egypt does not go up or enter, then no
rain will fall on them; it will be the plague with which the LORD smites the nations who do not go up to celebrate the Feast of Booths.
19This will be the punishment of Egypt, and the punishment of all the nations who do not go up to celebrate the Feast of Booths.
20In that day there will
be inscribed on the bells of the horses, “
HOLY TO THE LORD.” And the cooking pots in the LORD’S house will be like the bowls before the altar.
21Every cooking pot in Jerusalem and in Judah will be holy to the LORD of hosts; and all who sacrifice will come and take of them and boil in them. And there will no longer be a Canaanite in the house of the LORD of hosts in that day. Zech 14