While there's no explicit text that says Zechariah's prophecy is conditional, history clearly shows it never came to pass because Israel never met the conditions for it's fulfillment. And, Scripture well establishes that God's prophetic promises/curses are always conditional, depending on the actions of the people:
- God said Nineveh would be leveled in 40 days, which didn't happen due to its repentance.
- God said Hezekiah's death was imminent, but added 15 years to his life after Hezekiah repented.
- God intended to destroy the exodus Israelites but repented after Moses interceded on their behalf.
- God promised to gather His people anytime He scattered them for disobedience if they would first repent.
Therefore, when Israel failed to get their act together and fulfill Zechariah's prophecy, we shouldn't dismiss their failure to meet the condition of it's fulfillment and give the Israelites a pass by sending it down to the end of time as a future fulfillment by "literal Israel after the church is raptured" ...mainly because no such circumstance will come to pass.
Historicism firmly teaches things are going to get worse and worse until the Antichrist compels all to take the Mark of the Beast -- followed by a boycott against those who refuse and then a death decree -- at which time probation closes and the plagues fall, with the seventh plague being the simultaneous gathering of the dead and living saints to Jesus at His Second Coming, accompanied by a destruction such as the world has never seen -- which will bring about the fulfillment of all those OT and NT verses concerning an empty, desolate, dark, uninhabitable, totally destroyed planet littered with the bodies of the wicked who dropped dead "at the brightness of His coming".