The impending ruin facing the people is destined to be comprehensive and absolute, striking every populated area [רד״ק, מצודת ציון]. However, the primary purpose of this devastation is not merely the physical leveling of cities. Rather, it is the total uprooting of idol worship. Every center of idolatry, along with its altars and statues, is targeted for complete eradication. The descriptions of ruin point to a final desolation, where all tools of foreign worship will be forced to cease, cut down, melted away, and entirely erased [מצודת ציון, ביאור שטיינזלץ].
The relationship between the ruined cities and the shattered altars can be understood in two distinct ways. One approach views the destruction of the cities as being so massive and overwhelming that it inevitably results in the complete desolation of the altars and all associated practices [מצודת דוד, מצודת ציון]. Alternatively, the connection is one of direct cause and effect. In this view, the sweeping punishment is brought upon the world specifically because of the sins committed at these high places and altars [רד״ק].
The aftermath of this destruction carries a profound consequence that can be viewed through two different lenses. On a physical level, the ruin leaves the former sites of worship in a state of complete and utter desolation [רד״ק, מצודת ציון, ביאור שטיינזלץ]. Yet, on a deeper, spiritual level, the devastation serves to expose the guilt of the people. As the ruin unfolds, their sins will become undeniable and entirely visible [רש״י]. Ultimately, this harsh reality will bring the people to a painful awakening, forcing them to recognize and understand that they truly deserve the punishment that has fallen upon them because of their actions [מלבי״ם].