Interesting post, but I have a few questions.
"But perception management operations also include more passive tactics like using media to spread government propaganda—and these are the most difficult for the FBI to investigate."
Maybe the FBI should be investigating the US intelligence agencies, as they are the real masters of using the domestic media to spread gov. propaganda.
"Public opinion is how people know what behaviors to adopt to be perceived as "good" or as "bad" or to be perceived as ethical."
How exactly does one determine what the "public opinion" is on any issue? Polls run by corrupt media organizations with extremely small sample sizes?
"The FBI is looking at the fact that foreign nations have every incentive to want US citizens (potential voters) to think favorably of their nation. "
Isn't that what the US gov. has been doing via endless Hollywood propaganda for the last 50 years? The other governments are just now learning how to use the American playbook on perception "massaging," and it seems the U.S. politicos are not liking this turn of events.