Restricting a company from doing business as it likes within legal boundaries sounds pretty UnAmerican too.

True, but there is a middle ground. The users of the service could boycott or make their voices heard in other ways.

Of course when a single company has a near monopoly due to network effect they become a defacto government.

A government is defined significantly more than the ability to maybe tell you you can't say X or Y thing in their virtual space.

I could create a website and delete any comments I don't like. Many websites do. It's not unAmerican if I do it, nor is it unAmerican if Facebook does it. I would detest the possibility of government censure of my website or of Facebook's.

Facebook is not 'a website'. Its a hosting service for lots of collaborative websites. Clearly debatable whether its more like an ISP than a publisher.

So you think the government should regulate speech on Facebook. Google too? How about Hacker News? Where exactly are you drawing the line?

Not every action by a country must be taken by the government. Being un-American is in fact something that the government must tolerate under the First Amendment. However, if you believe that American culture and values creates a good society, and that freedom of speech is a cornerstone of that culture and values, then you can use your freedom of association to boycott Facebook for being un-American.

I'm not talking about boycott. Boycott all you want. He said that the government should censure Facebook. He's dead wrong. Can't even believe I'm having this argument on here.