A shrug can mean "I don't know", but it's primary meaning is indifference. Just prior to "The report amounts to a giant shrug" the article said, "Few in the Pe

A shrug can mean "I don't know", but it's primary meaning is indifference. Just prior to "The report amounts to a giant shrug" the article said, "Few in the Pentagon seem worried about extraterrestrial invaders." It is just as likely, if not more so, that the writer meant indifference and not "we don't know". We'll never know, however, since the word isn't clear from the context.