The Israelites arrive at the cities of the Gibeonites fully prepared and intending to launch a military strike. According to Torah law, the Israelites are obligated to destroy them. Because the Gibeonites never explicitly accepted terms of taxation and servitude, the commandment to leave no soul alive remains fully in effect.
Despite this clear directive, the nation refrains from attacking because their leaders actively intervene to stop them. From a purely legal standpoint, the oath the leaders had sworn to the Gibeonites should not have applied to the people at all. The agreement was obtained through a mistake and stood in direct contradiction to a commandment from the Torah. Nevertheless, the leaders hold the people back to prevent the desecration of God's name, as the oath had been sworn using His name [מלבי״ם].
This decision to halt the attack sparks intense frustration among the Israelites, leading to severe complaints and resentment [מצודת ציון, ביאור שטיינזלץ]. The people direct their anger squarely at the leaders. They argue that the leadership is needlessly surrendering the nation's rights and military power [ביאור שטיינזלץ]. Furthermore, they are furious that they are being prevented from fulfilling a direct command from God simply to uphold an oath made in error [מלבי״ם].