Back in the day, if the enemy wanted to learn about naval deployments and troop movements, he had only to hang around the base beauty parlors or bars near the main gate. After a couple of days, the wily enemy would have all the intel he could handle.
The only problem for him would be sifting through the beer talk to get the few grains of fact from all the alcohol addled speculation. Everyone knows a ship is going to sea. Some missions the only person who knows the purpose is the Captain and he may not even have the full picture.
My mom kept a bunch of old letters from my Dad. They had developed a “code” of sorts about where he was headed, etc. Lots of made up relatives with my dad asking questions like “Are you going to Harry’s house for Thanksgiving, and then on to Elaine’s like you usually do?” (Heading to Hawaii, then Einewetok).
I’ll have to ask my mom when I give her a call if she ever let those secrets out to others. I suppose she did to my Dad’s mother and father, at the least.