Correction to the above post. The following sentence:
Remember, the writer is trying to make Jesus sound like he is foretelling the destruction of the Second Temple, an event that happened AFTER the gospels were composed...
Should read:
Remember, the writer is trying to make Jesus sound like he is foretelling the destruction of the Second Temple, an event that happened BEFORE the gospels were composed...
The gospel of Mark was composed around the time the Second Temple fell, in 70 CE. The Jewish Christians at the time were hoping that a void would open up that would grant them legitimacy with the Romans as Judaism was legal under Roman law, but Christianity was not.
With the Temple gone, the first Christians (who were of Jewish origin) tried to take the name "Jew" exclusive to themselves before Roman authority. As such, they claimed that Jesus was a prophet and as proof, claimed he "foretold" the victory of the Roman army over Jerusalem symbolized by the Temple's fall.
This attempt backfired in Rome. The Romans had no hatred of the Temple and tried to save it. It caught fire in the siege by mistake. Judaism was still legal throughout the empire after the event.
Also the Jews were not driven away from Jerusalem. It was allowed to prosper with its Jewish population while Christians became the object of persecution. But then Bar Kokhba arose as prince, Jerusalem declared independence from Rome, and then, and only then, were the Jews banned from Jerusalem in 135 CE. But Christians still got no religious freedom and never did get to replace the Jews as they had hoped (not to mention did their Christ ever return during that promised generation).
Mark's Temple prophecy gets extended into Matthew's Parousia prophecy in his revisionist gospel and as happens in Luke's "times of the Gentiles" prophecy. It gets totally dismissed, however, by John who elevates Jesus to God status in his opus, described as someone who has been ruling as God forever and ever anyway.