The sheer shock and terror of war can paralyze even the deepest human instincts. As an enemy army approaches, the overwhelming noise of its advance acts as a weapon of its own, designed to instill a crippling fear in the hearts of those under attack.
The terrifying assault begins with the sound of the enemy's powerful horses. The primary approach among commentators is to view this noise as the heavy stepping and pacing of the steeds, though some specifically describe it as the violent, forceful striking of hooves against the earth in a fierce gallop [רד״ק, מלבי״ם]. Joining this rhythmic pounding is the deafening roar of the chariots and the loud rumbling of their wheels. Together, the clashing sounds of iron hooves and spinning chariot wheels are deliberately calculated to shatter the courage of the victims [מצודת דוד, ביאור שטיינזלץ].
The result of this overwhelming anxiety is tragic and almost unthinkable. The sheer panic completely paralyzes a father's natural compassion for his children, leaving him unable to even look back to save them. To highlight the magnitude of this psychological collapse, the [מלבי״ם] contrasts this event with a natural disaster. During a flood of water, a father's immediate instinct is to rush in and rescue his children. However, when faced with a flood of invading enemy troops, the terror is so absolute that it entirely erases this parental drive. This tragic helplessness stems from a profound weakness. It is not merely a physical failing, but a state of complete despair—a total loss of the mental strength required to stand against the enemy or take any action to survive the battle [מצודות, רד״ק, ביאור שטיינזלץ].