Laws are words

Laws consist of words, but making a law is something different than just saying something. It is an act, and indeed American laws are often (or always?) called Acts.

First of all, I think we can definitely say that certain words are bad. if somebody is saying that they want to have sex with a child, we can tell them this is something bad and that we don't agree with this.

And pretty much all countries in the world limit what we can say. You're not allowed in the US to, for example, threaten the US president with murder, even if it's just words.