The following excerpt encourages respectful debate, instead of blindly going along with a leader's plans:
"Relations among all leaders—from corporal to general— should be based on honesty and frankness regardless of disparity between grades. Until a commander has reached and stated a decision, subordinates should consider it their duty to provide honest, professional opinions even though these may be in disagreement with the senior’s opinions.
"However, once the decision has been reached, juniors then must support it as if it were their own. Seniors must encourage candor among subordinates and must not hide behind their grade insignia. Ready compliance for the purpose of personal advancement—the behavior of “yes-men”—will not be tolerated.""
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The idea of erring toward respectful disagreement when warranted with leaders, instead of being a yes-man, has helped me greatly with building trust in teams I've worked with in the past.
However, I don't believe that it's always the best approach that "juniors then must support [decisions they disagree with] as if it were their own." I get that you can seem less confident by saying "{My manager} wants us to take this approach," instead of saying "We're taking this approach."
But for decisions that you personally disagree with, the best approach would include an acknowledgement of the downsides. Phrasing might be: "We're doing this because of XYZ reasons from the leadership, while acknowledging the downsides ABC."
I believe that this phrase is balanced: it avoids directly saying that you disagree with the decision (which can lead to people implementing the decision poorly, possibly making it doomed even if it turns out to be the correct one), while also acknowledging potential downsides (because the juniors are likely to see them too). An expression as if the decision were truly your own might mean an enthusiastic delivery without acknowledging the downsides, which reduces your own credibility with your direct team.
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In any case, I believe that reading about the approach—even if one doesn't agree with every idea—is a worthwhile exercise, as I've found that much of the principles remain relevant across vastly different organizational environments.
[1] (1997) https://www.marines.mil/Portals/1/Publications/MCDP%201%20Wa...