-- 1919: Radio technology becomes more sophisticated because of improvements made during World War I and becomes capable of reaching mass audiences. The number of U.S. radio stations grows from five in 1921 to 700 by 1927.
-- 1920s: Consolidation starts in newspaper industry. Chain ownership becomes more common as Linotype machine and rotary press speed up productivity and national advertising grows. Press barons political and business ambitions multiply.
-- 1923: Newsmagazines are born and play a role in news gathering and reporting after Henry Luce and Briton Hadden launch Time and introduce group journalism," synthesizing weekly newspaper and wire service reports. Newsweek and other competitors follow
-- 1927: Radio Act of 1927 declares air waves public property subject to government licensing -- a change in the traditional "hands-off" relationship between government and print press. The Federal Radio Commission, later to be renamed the Federal Communication Commission, is created.
-- 1930s: The Depression hurts newspapers, partly because advertisers switch to radio ads. Reporters, whose average wage is $30 a week, found the American Newspaper Guild.
-- 1934: Guild adopts a code of ethics that calls for fair and accurate reporting and objectivity.
-- 1938: First TV sets available, but World War II delays development.
-- 1948: 172,000 U.S. homes have TV. By 1958, total is 42 million.
The limits of objectivity: The 1950s
-- 1950-54: Sen. Joe McCarthy tests the limits of "objectivity" with witch hunt, hearings and blacklists of alleged communists in government and elsewhere. Few newspapers investigate claims, but TV exposes McCarthy with Edward R. Murrow's half-hour broadcast in March 1954. Senate censures McCarthy in December; he dies of alcoholism three years later.
-- 1952: Eisenhower-Stevenson 1952 presidential race is first to provide advertiser-sponsored campaign coverage.
-- 1961: Relationship between journalism and government changes dramatically after failed 1961 Bay of Pigs invasion by Cuban exiles, and the New York Times becomes a subject of angry internal debate for downplaying CIA links to invasion, in response to a Presidential request. President John F. Kennedy later says he wishes the Times had reported all it knew.
-- 1963: NBC and CBS increase nightly news broadcasts from 15 to 30 minutes.
-- 1968: Walter Cronkite departs from his traditional neutrality after Tet Offensive, and gives a frank on-air critique, saying negotiation is the only rational way out of the Vietnam War. The civil rights movement, peace marches and Kennedy assassinations contribute to a move away from objectivity to advocacy journalism. The TV news show 60 Minutes debuts on CBS.
Adversarial press: The 1970s
-- 1970: Journalists begin to reflect the country's lack of consensus about the Vietnam War as more people and politicians doubt chance of military success. White House illegally wiretaps journalists in a failed attempt to stop leaks.
Most dailies scale down space devoted to strictly political and economic news and restructure with more features and "Living" sections as Baby Boomers, the first TV generation, reach adulthood without developing their parents' newspaper habits. The impact of more women in the workforce and a growing move to the suburbs means more commuting time and less time with the newspaper.
Fewer than 10 percent of American homes have cable TV, but the percentage will grow to 53 percent by 1989. Within a decade, CBS, NBC, ABC will face competition from emerging new networks.
-- 1971: New York Times and Washington Post publish the Pentagon Papers, detailing a pattern of arrogance, missteps and lies about extent of U.S. military engagement in Southeast Asia. U.S. Supreme Court allows further publication, ruling that the constitutional guarantee of a free press overrides government concerns. The New York Times wins a Pulitzer.
-- 1972: Washington Post wins Pulitzer for Watergate investigation by Carl Bernstein and Bob Woodward.
Compiled from "American Journalism in Historical Perspective," an essay by Michael Schudson and Susan E. Tifft in "The Press," a 2005 anthology, published by Institutions of American Democracy Series, a joint project of The Annenberg Foundation Trust at Sunnylands and The Annenberg Public Policy Center of the University of Pennsylvania.
