In moments of national crisis and collapse, the profound weakness of human leadership is exposed when it is disconnected from a spiritual foundation. The people reach a breaking point, a moment of stark realization where they recognize the utter futility of relying solely on their monarchy.
The primary approach among commentators is that this realization occurs during a time of acute trouble, as an enemy attacks and disaster overtakes the nation, much like the final, unstable years of the Kingdom of Samaria [רש״י, מצודת דוד, ביאור שטיינזלץ]. Alternatively, this cry is understood as a later, painful confession made by the Israelites after they have already been driven into exile [רד״ק].
When the people declare their lack of a true leader and question what a king could even do for them, their words reflect a deep sense of disappointment and helplessness. They finally understand that the human ruler they trusted to lead them into battle is entirely powerless against their enemies. They remember that in the past, when they followed God's will, He acted as their true King and delivered them. However, because they abandoned the Torah, their earthly king lacks the strength to save them from God's anger [רש״י, רד״ק]. The fear of God and the authority of a king are deeply connected; without reverence for God, a human ruler loses all ability to bring salvation to his nation [מצודת דוד].
Beyond military failure, this situation reflects a state of complete social collapse and anarchy. In a society fractured by divided hearts and devoid of the fear of God, the natural respect for human authority also vanishes. As a result, individuals simply do whatever they please, and the king's power is entirely erased [אבן עזרא, ביאור שטיינזלץ].
Taking a distinctly different perspective, the people's words can be seen as an ideological rebellion rather than a cry of despair. In this scenario, the king actually desires to abolish idol worship and guide the nation back to serving God. However, the people rise up against him, openly declaring that they have no desire to fear or serve God. Their question of what the king can do to them is a direct challenge, mocking the idea that any ruler could force them to change their ways. This view fundamentally shifts the blame for idol worship away from the leadership, placing the responsibility squarely on the shoulders of the people who freely choose it [מלבי״ם].