[dllthomas]

> as part of the US Government arguably the first amendment applies directly to [the Post Office]

Quite fair.

As to the rest of it: I agree with your description of how things work, but I don't think it really addresses the point I was trying to make which (made more explicit and construed narrowly) is that we need to be more precise about the situation before we say "compelling carriage of speech is tyranny".

[ashtonkem]

To re-summarize my point; arguably even common carriers aren’t actually forced by the government to be content neutral. Rather they’re given certain benefits (such as the right to sell to the public without contract) in exchange for meeting certain standards of behavior, including content neutrality and regulations on rates and liability. Companies are free to reject those restrictions, but they lose access to the benefits as well.