Edit: I misread your comment, but I'm leaving the advice. Normalizing the militarization of police shouldn't be accepted.

For anyone looking for an answer to how to reach your kids about the world and cut through the propaganda, just talk to your kids. Talk to them like peers (don't talk down to them) and listen to what they have to say. Show them the basic respect adults expect that children rarely get from adults.

If you do this throughout their lives, you won't win every subject, but they'll listen to you and it will facilitate these types of conversations. Don't shy away from difficult and uncomfortable topics. They'll learn. They'll also learn to see these things for themselves if you explicitly teach them and share the books that helped inform you.

Teenagers in particular are at the perfect age to start seeing through the BS. Kids will buy into propaganda constantly, but you can cut through it with them by building a strong relationship of communication.