[krajzeg]

There is a lot of discussion below on whether 451 is the right error code and how to implement it properly, but I'm missing one thing - what's the benefit of doing it as a status code at all?

If you're going to say that it raises censorship awareness - Internet protocols are intended as useful technical standards for programs to communicate, not vehicles for political goals.

What is the technical benefit of failing with a different error code? Is there need for client software to react differently to a 451 and a 403? The status code is not intended for the human user. If we want to raise awareness, than we already have means to do that - a 403 with a descriptive page citing the reasons. Many websites already do that when complying to DMCA takedowns.