I 've been told a story that was only passed on to me by word of mouth, but since I have no actual cites I won’t post it. Does anyone here know where this phrase actually came from, and if so, have a cite to verify it?
It was a poster campaign by the US government . Here are more details :-
http://www.state.nh.us/ww2/loose.html
The British government ran a similar scheme . One of the most famous phrases was " Be Like Dad , Keep Mum."
Here is a link to some British posters :- http://www.homesweethomefront.co.uk/web_pages/hshf_careless_talk_pg.htm
Most references simply expalin it as a slogan. Ben Sullivan’s Wise Old Sayings site goes a bit further, laying out this explanation:
Unless some ancient advertising history can lay claim to identify the actual author, I suspect that it will remain one of those clever slogans that make it into the public consciousness anonymously. (I would be really leary of any claims that it was tied directly to any specific sinking of any particular ship(s). WWI had already produced a number of ads (none quite so catchy) that explained that gossiping about troop movements could be used by German spies to set up attacks on our military.)
One of my favorite WWII phrases is rumored to have been emblazened on a giant banner at Bletchley Park: “THE ENEMY IS LISTENING.”
Especially funny because Bletchley Park is where Alan Turing, et al, listened to the enemy.
By March of 1942, the phrase “loose lips” was used by the Navy in talking about troop movements, ship departures, etc.
By May of that year, there were civil defense placards posted in every town saying “loose lips might sink ships.”
By July, the phrases “keep mum, chum” and “loose lips sink ships” were in newspapers in the US.
Here are some representative posters with messages about civilian information security.
THIS is what happens when YOU talk to others about Ship Sailings
A careless word…A NEEDLESS SINKING
None with the elusive “Loose Lips Sink Ships,” however, although I know I’ve seen such a poster. As Samclem notes, this phrase also appeared in wartime papers. They often printied war slogans as “column filler”. Other common themes for both posters and column filler slogans:scrap and recycling drives, buying war bonds, increasing production, women in industry, rationing, characterizations of either allied troops or the enemy.