NO.

The Bill of Rights are enumerated protections FROM THE GOVERNMENT.

The concept of "Freedom of Speech" is different and more broad than the First Amendment to the US Constitution, but a private entity not protecting it is not a violation of the First Amendment or any other 9. Yes, the double-negative is important.

Facebook's content policies are not subject to the Bill of Rights, which constrain only the government.

For a historical viewpoint, simply look at how often the German Nazi party would change what classifies as being a Jew or "undesirable". It was only ever about putting fear into people and maintaining control. They had no real opinions on why these people were undesirable - those could be made up after the fact.

If Nazism was an opinion, I would be willing to defend it. But it's not, and it thrives when it's given the legitimacy as such.

EDIT: To try and tie this back to the topic at hand, are blatant lies still "opinions"? What about death threats and hate speech? My point is simply that we already make distinctions about what kind of speech is free, so I feel that Facebook instituting policies that align with these existing rules makes sense - even though I feel that they are becoming too large to be the de-facto source for information on the Internet.

Can you provide any links? My google-fu is failing me.