What one says can make an enemy sympathizer happy to hear. A mother could talk about the socks she's knitting for you grandson, a father could talk about the truck's engine being hard to start (with no other details), but it was forbidden to talk about things that give away troop movements or anything that might be useful to the enemy. They would love to know that there were ships leaving the Baltimore harbor. The submarines would be there waiting for them.
In some cases it would be considered to be treason to divulge certain information, so your freedom of speech is severely limited.
