[Enginerrrd]

>and the other is not

Sort of... The feds usually drop hints before cracking down with a heavier hand, and I don't think this is that far removed from it. So there's a bit of an implicit threat.

Even if you disagree with that assessment, however, it's worth noting that the 1st amendment specifically bars congress from making law which would infringe on freedom of speech. So, IMO, it's a bit improper for them to write pseudo-official letters asking for censorship.