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Bravery is by far the kindest word for stupidity, don’t you think?
— Mycroft ‧ Sherlock

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Here bravery gets a sly demotion: the speaker suggests that what people praise as courage is often just foolishness with better public relations. It's a dry, sneering bit of wordplay, asking the listener to agree that "brave" is the polite label for a bad decision.
Context reviewed