...[A]fter adopting a policy, decisionmakers should resist the temptation to marginalize any skeptics. Indeed, it may be advisable for someone to deliberately play the role of "devil's advocate" and question optimistic appraisals of likely outcomes. Following the 2002–03 decision to invade Iraq, U.S. war planners were extremely overconfident about the prospects for stabilizing the country. Skeptical voices were sidelined or excluded. If senior officials had anticipated the shift to implemental mind-sets and the associated overconfidence, a "devil's advocate" would have helped to challenge shaky assumptions behind the strategy.