Why did God bring the Roman army under Titus against Jerusalem?

Les explains that this was discipline again, so God brought in the Roman army under Titus. Titus besieged the city, and when he finally gained entrance, it was the greatest mayhem man could imagine. The Roman legions destroyed the Jews by the thousands, took the temple down rock by rock and stone by stone, just as the prophet had written would happen. Israel was then dispersed into every nation on the face of the earth. Later, they began returning, set up kibbutzes, and the nation of Israel reappeared until 1948, when Harry Truman became the first world leader to declare Israel a sovereign state. Les also stresses that God’s mercy would never depart from the nation of Israel.