Differences and difficulties in interpretation have characterized much of the later history of the 1st Amendment. For example, the amendment prevents Congress from making any law regarding the "establishment of religion," but this clause has been interpreted either as barring the government from giving preferment to any particular religion or as requiring a complete and total separation of church and state. Moreover, in spite of the apparent absolute prohibition in the amendment's language "Congress shall make no law...," Congress has, in fact, many times passed laws "in the public interest" that restrict freedom of speech and press. Among the most famous of these acts are the Alien and Sedition Acts (1798), the Smith Act (1940), and the McCarran Act (1950). In addition, federal agencies and prosecutors have initiated actions that, where allowed, have resulted in certain limitations on freedom of speech and press.
In ruling on the constitutionality of various restrictions on these civil rights, the Supreme Court has at various times tended to support either the rights of the individual or the interest of society. Since the early 1950s, however, the Court has also followed a balancing approach whereby the private and public interests are weighed in each case.
Berns, Walter, The First Amendment and the Future of American Democracy (1976)
Chafee, Zechariah, Jr., Free Speech in the United States (1941; repr. 1971)
Corwin, Edward S., Edward S. Corwin's The Constitution and What It Means Today, ed. by Harold Chase and Craig Ducat, 14th ed. (1978)
Emerson, Thomas, The System of Freedom of Expression (1970)
Hentoff, Nat, The First Freedom (1980).