Why does yahoo censor questions in violation of the constitutional ammendment of freedom of speech.?

How does this differ from a totalitarian regime. Other than extreme obscenity which is often visible together with racist and vulgar remarks, why does yahoo censor anyone and what gives a few hidden people in that organization the right to practice this unamerican activity. " We may disagree with what you say, but we'll fight for your right to say it." An American saying. Gimme a break Yahoo.! I get three best answers and spend my valuable time trying to give positive advice on this site and you violate me twice. Who do you people think you are.!?