Encryption at Rest Private Messages?

[Ocean West]

Should the body content of private messages be encrypted in the database, and only decrypted when the users in the thread is reading the message?

[sudo]

Why?

You would need to save the decryption key on the server so if a hacker got into your system they would be able to get the key anyway and it would also break the ability to search the messages without a LOT of work.