I forgot to mention , that WAR could be World War III, a fuel scale Nuclear War. The city of Jerusalem half them population goes into voluntary Exile. Most are killed, EXCEPT for the 144,000 sealed by the Holy Spirit, flews the to the East into Jordan after HIS feet touch down on the Mt. of Olives. He sends them out, through that Valley after the mountain splits to a place of safety. AND TURNS to the Valley of Megiddo to end ALL WHO ARE TRYING TO STOP HIS RETURN.
Rev. 14:20 – Then the press was trampled outside the city, and blood flowed out of the press up to the horses’ bridles for about 180 miles. (HCSB)
That is How many combatants on in that VALLEY that are killed instantly.
Zechariah 14:12 (HCSB)
12 This will be the plague the LORD strikes all the peoples with, who have warred against Jerusalem: their flesh will rot while they stand on their feet, their eyes will rot in their sockets, and their tongues will rot in their mouths.
YES, I believe that all is to be interpreted LITERALLY.