Divine punishment for the sins of a nation's leadership can arrive with startling speed and absolute precision. A foreign army swept into Judah and Jerusalem, driven not by typical ambitions of conquest, but acting as an instrument of targeted justice against those who abandoned God. This invasion occurred exactly as the year completed its cycle [ביאור שטיינזלץ]. The disaster arrived without delay [מלבי״ם], falling precisely one year after the murder of the prophet Zechariah [מצודת דוד]. The people of Judah faced this severe judgment because their sins of forsaking God surpassed those of the other tribes [רש״י].
In the past, King Joash successfully bribed the king of Aram with treasures to retreat. Now, however, the Aramean military forces advanced on their own, even without their king present. This turn of events directly fulfilled Zechariah's warning that abandoning God inevitably leads to ruin [מלבי״ם]. The attack was aimed squarely at King Joash himself [ביאור שטיינזלץ].
As the Arameans struck, they specifically killed and destroyed the nation's officers. This focused assault served as a precise measure for measure punishment. Following the death of Jehoiada the priest, it was these very officers who bowed to Joash and led him into sin. Consequently, the disaster struck them directly [רש״י, מצודת דוד].
The fate of the common people during this invasion is understood in several ways. One perspective suggests that the Arameans intentionally separated the officers from the general population, executing only the corrupt leaders while leaving the rest of the people unharmed. This highlights the highly focused nature of God's punishment against those who led the king astray [מצודת דוד]. Conversely, others explain that the king, his officers, and a large army went out to battle, and while the Arameans killed the leadership, they also inflicted heavy casualties among the common citizens [רד״ק, ביאור שטיינזלץ]. A third approach notes that the destruction was so absolute that the people effectively ceased to function as a unified nation or a capable military force [רש״י, ביאור שטיינזלץ]. When the military campaign concluded, all the gathered spoils were shipped away to the king in Damascus, the capital city of Aram [ביאור שטיינזלץ].