On the one hand, our history is filled with examples of overt government censorship, from the 1873 Comstock Law to the 1996 Communications Decency Act. On the other hand, the commitment to freedom of imagination and expression is deeply embedded in our national psyche, buttressed by the First Amendment, and supported by a long line of Supreme Court decisions. Once you allow the government to censor someone else, you cede to it the the power to censor you, or something you like. Freedom of expression for ourselves requires freedom of expression for others. It is at the very heart of our democracy.
Many examples come to mind.
Why the Caged Bird Sings to John Steinbeck's Grapes of Wrath , have been banned from public schools based on their sexual content. A museum director was charged with a crime for including sexually explicit photographs by Robert Mapplethorpe in an art exhibit. No causal link between exposure to sexually explicit material and anti-social or violent behavior has ever been scientifically established, in spite of many efforts to do so. This does not mean that all sexual expression can be censored, however. Nevertheless, even the relatively narrow obscenity exception serves as a vehicle for abuse by government authorities as well as pressure groups who want to impose their personal moral views on other people.