Thirty-four years ago, a previously inconsequential newspaper in San Antonio, Texas, began warning of the imminent arrival of "killer bees." Banner headline after banner headline sought to terrify the reading public with the prospect of these swarming, aggressive creatures, steadily advancing from South America into the United States. By now, we know that the feared infestation has slowly spread into the Southwest, causing a grand total of about 15 deaths. The most lasting effect of the killer bees was to inspire a classic John Belushi-Dan Akroyd sketch on Saturday Night Live. Unfortunately, the San Antonio publisher who gave us killer bee hysteria has stuck around, becoming a threat to the republic, or at least to civilized standards of journalism. I speak, of course, of media mogul Rupert Murdoch, lately in the news with a $50 billion bid to buy Dow Jones and thus to control its flagship newspaper, The Wall Street Journal. An Aussie turned Brit turned American, Murdoch is the sort of plutocrat who masquerades as a populist. But his gutter-dwelling brand of journalism hardly qualifies as vox populi, the voice of the people. It, and he, are more like a pox on the populi. Murdoch's apologists like to portray criticism of him as defense of an incurably liberal media establishment. But his toxic effect on journalism has nothing to do with his right-wing politics. There are legitimate and credible opinion magazines, and also daily papers such as the New York Sun, that manage perfectly well to espouse conservatism without disgracing journalism. The Wall Street Journal, after all, already has an editorial page that serves as the semi-official voice of the conservative movement. PLAIN AND simple, Murdoch is all about sleaze. Or, actually, he's about something even worse than sleaze in the long run. His style of blatantly ideological journalism would push America closer to the Western European model, in which editorial bias pervades news coverage and the whole notion of non-partisan, reportorial coverage is seen as laughably naive. From his perch on the political Right, Murdoch shares with the Left-leaning blogosphere a disparaging, dismissive attitude toward the traditional news organizations, such as Dow Jones, that are fashionably derided as the "MSM," the mainstream media. American journalism, it is true, began with unapologetically partisan pamphlets and broadsides. The concept of the journalist as reporter and fair broker only emerged late in the 19th century. And such publishers as Joseph Pulitzer and William Randolph Hearst practiced sensationalism alongside substance. Murdoch, however, stands alone as the catalyst for three of the worst trends in American journalism. He created the archetypes for the reactionary tabloid (The New York Post), the tabloid-TV show (A Current Affair), and the politically driven cable network (Fox). Because they are perceived as being profitable, his models have inspired imitators and enticed once-reputable news organizations to jump into the muck. In fact, some of Murdoch's pet projects have not been especially successful in the marketplace. The New York Post, which published non-fiction prior to Murdoch's purchase in the late 1970s, has lost tens of millions of dollars in his quest to kill off its main competitor, the Daily News. A scrappy paper with deep roots in working-class New York, the Daily News has awkwardly struggled to maintain its integrity (it won a Pulitzer Prize for editorial-writing this year) while trying to match Murdoch contest for contest, crime for crime, celeb for celeb. In the arena of cable news, the supposed phenomenon of Fox has an audience very low in the millions. But instead of seeing Fox for what it is - a political movement pretending to be a news organization - networks like CNN and MSNBC have begun aping its jingoism and its deliberate blurring of news and commentary. The anti-immigrant demagoguery of Lou Dobbs on CNN would be unthinkable without the precedent of Fox. The fact that Murdoch is willing to lose vast sums on properties such as the Post points to the larger danger in his prospective acquisition of Dow Jones. More than a profit center, he wants a bully pulpit, a prominent podium for his right-wing agenda, a chance to play kingmaker on the national stage in the same way he has tried to be for New York's mayors and governors. For the moment, the Bancroft family that owns the controlling shares of stock in Dow Jones appears to be standing intact against Murdoch's lavish offer. Even if fended off for now, though, the Murdoch assault can only destabilize an industry already reeling from declining readership and advertising amid epochal technological change. Both The Washington Post and The New York Times have families in charge, and the Times has been criticized by some large institutional investors for its two-tiered system of shares, which leaves all significant decision-making with the Sulzberger clan. I have never accepted the premise that family ownership means quality while chain ownership means mediocrity. The Gannett chain, a frequent whipping boy in such arguments, built USA Today from a laughing stock into a respected national paper. The Knights and Ridders, once perceived as enlightened owners, have downsized and sold off such fine papers as The Philadelphia Inquirer and The San Jose Mercury News. Whether a family or a chain, the best owners understand that journalism, even as a profit-making venture, is also a public trust. For Rupert Murdoch it has been nothing but a public trough. The writer is a professor of journalism at Columbia University.