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by pja
4722 days ago
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WWII I believe: http://www.altus.af.mil/news/story.asp?id=123266336 If you do a google ngram search on the phrase, you'll see a blip during WWII and then nothing until 1970. I'm guessing the use from 1970 onwards probably carried the negative connotation we're all familiar with. |
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