Joe Sutter was the chief engineer on the Boeing 747. He worked hard; stuck by his guns under fire; and consistently did what he thought was right, even when doing so risked his job. His account of the design and building of the 747 is a must read, not just for engineers but for managers and leaders of all stripes.
What does this have to do with red teaming? Joe was precisely the kind of leader you want standing behind your red team. Red teams can uncover unpleasant information—information that can challenge the system’s stakeholders and provoke them to resist. In such cases, stakeholders can sometimes shut the red team down or maneuver it into irrelevance. That’s when your red team needs a leader who will fight to preserve the red team’s mission, relevance, and reputation without allowing the political tension to spill over into the red team’s activities.
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Every member should have a chance to input their thouhgts. Every member should be able to poke holes into the Leader's plan. That's the way good planning happens. A Leader is a Leader only if the people he/she leads allow him/her to lead. Remember that.