The push by federal regulators to break up Microsoft is big news. Until recently, the software giant seemed untouchable -- and few people demanded effective antitrust efforts against monopoly power in the software industry. These days, a similar lack of vision is routine in looking at the media business.

Today, just six corporations have a forceful grip on America's mass media. We should consider how to break the hammerlock that huge firms currently maintain around the windpipe of the First Amendment. And we'd better hurry.

The trend lines of media ownership are steep and ominous in the United States. When The Media Monopoly first appeared on bookshelves in 1983, author Ben Bagdikian explains, "50 corporations dominated most of every mass medium." With each new edition, that number kept dropping -- to 29 media firms in 1987, 23 in 1990, 14 in 1992, and 10 in 1997.

Published this spring, the sixth edition of The Media Monopoly documents that just a half-dozen corporations are now supplying most of the nation's media fare. And Bagdikian, a longtime journalist, continues to sound the alarm. "It is the overwhelming collective power of these firms, with their corporate interlocks and unified cultural and political values, that raises troubling questions about the individual's role in the American democracy."

I wonder what the chances are that Bagdikian -- or anyone else -- will be invited onto major TV broadcast networks to discuss the need for vigorous antitrust enforcement against the biggest media conglomerates. Let's see:

• CBS
  Not a good bet, especially since its merger with Viacom (one of the Big Six) was announced last fall.

• NBC
  Quite unlikely. General Electric, a Big Six firm, has owned NBC since 1986.

• ABC
  Forget it. This network became the property of the Disney Co. five years ago. Disney is now the country's second-largest media outfit.

• Fox
  The Fox network is owned by Rupert Murdoch's News Corp., currently number four in the media oligarchy.

And then there's always cable television, with several networks devoted to news:

• CNN
  The world's biggest media conglomerate, Time Warner, owns CNN – where antitrust talk about undue concentration of media power is about as welcome as the Internationale sung at a baseball game in Miami.

• CNBC
  Sixth-ranked General Electric owns this cable channel.

• MSNBC
  Spawned as a joint venture of GE and Microsoft, the MSNBC network would see activism against media monopoly as double trouble.

• Fox News Channel
  The Fox cable programming rarely wanders far from the self-interest of News Corp. tycoon Murdoch.

Since all of those major TV news sources are owned by one of the Big Six, the chances are mighty slim that you'll be able to catch a discussion of media antitrust issues on national television.

Meanwhile, the only Big Sixer that doesn't possess a key U.S. television outlet -- the Bertelsmann firm based in Germany -- is the most powerful company in the book industry. It owns the mammoth publisher Random House, and plenty more in the media universe. Bertelsmann "is the world's third largest conglomerate," Bagdikian reports, "with substantial ownership of magazines, newspapers, music, television, on-line trading, films, and radio in 53 countries." Try pitching a book proposal to a Random House editor about the dangers of global media consolidation.

Well, you might comfort yourself by thinking about cyberspace. Think again. The dominant Internet service provider, America Online, is combining with already-number-one Time Warner -- and the new firm AOL Time Warner would have more to lose than any other corporation if a movement grew to demand antitrust action against media conglomerates.

Amid rampant overall commercialization of the most heavily trafficked websites, AOL steers its 22 million subscribers in many directions -- and, in the future, Time Warner's offerings will be most frequently highlighted. While seeming to be gateways to a vast cybergalaxy, AOL's favorite links will remain overwhelmingly corporate friendly within a virtual cul-de-sac.

Hype about the New Media seems boundless, while insatiable old hungers for maximum profits fill countless screens. Centralization is the order of the media day. As Bagdikian points out: "The power and influence of the dominant companies are understated by counting them as 'six.' They are intertwined: they own stock in each other, they cooperate in joint media ventures, and among themselves they divide profits from some of the most widely viewed programs on television, cable and movies."

We may not like the nation's gigantic media firms, but right now they don't care much what we think. A strong antitrust movement aimed at the Big Six could change such indifference in a hurry.

Norman Solomon is a syndicated columnist. His latest book is The Habits of Highly Deceptive Media. Media activism link: http://www.fair.org