Groupthink often manifests through several key behaviors: 1. Illusions of Invulnerability: Overconfidence within the group can lead to taking excessive risks. 2. Rationalization: Group members may rationalize warnings that challenge the group’s assumptions. 3. Suppression of Dissent: Dissenting opinions are suppressed to maintain group harmony. 4. Self-Censorship: Members withhold their opposing views. 5. Illusion of Unanimity: Silence is perceived as consent.