Group-think is a type of thought exhibited by group members who try to minimize conflict and reach consensus without critically testing, analyzing, and evaluating ideas. During Group-think, members of the group avoid promoting viewpoints outside the comfort zone of consensus thinking.
Among evangelicals, known for their cultural checks and balances and ridiculously strong peer pressure, group-think is so prevalent that it almost manifests itself as a hive-mind. Their conformity of thought, enhanced by their fellowship and world-view, brings about such uniformity in perception that dealing with one evangelical drone, is pretty much the same with the next.
As a control mechanism within the evangelical community, it's prevalence ensures that their fellowship is safely guarded, regardless of differing viewpoints. As proof, I will use Irving Janis' eight symptoms of group-think and offer the equivalent of them in the evangelical context.
1. Illusions of invulnerability creating excessive optimism and encouraging risk taking.
This is would prevalent in many ministries, they encourage their adepts in trying to evangelize everything that isn't bolted down. Open-air ministries are a classic example of this. These are re-enforced by the "divine right" that is constantly uttered by the elders.
2. Rationalizing warnings that might challenge the group's assumptions.
This is often found in the form of when other Christian groups who question their methods, this leads often to an appeal to authority combined with an appeal to emotion using the alleged veracity of the bible, often leading to much heated debates in the matter of interpretations. When dealing with non-christians, it takes the form of painting said unbelievers as over-reacting.
3. Unquestioned belief in the morality of the group, causing members to ignore the consequences of their actions.
This leads to some of the ridiculous extremes of evangelism, like doing missionary work in a war-torn country (and expect the government to bail them out when they get in trouble) or in other cases, even show complete disregard for laws (seperation of church and state) and basic human rights.