While the rest of us were busy last weekend consulting Nancy Reagan's astrologers over whether New Jersey Devils coach Jim Schoenfeld really pushed Mila Mulroney, or just called her names (or have I got that wrong?), Conrad Black was reminding us of a more pressing public issue: the influential role in modern society of the media that report these items. Yes, it's Awful Power of the Media (APM) time again.

''The media have no rival, no countervailing force . . . as an antidote to their potential for capricious manipulation of public opinion,'' the transatlantic press baron and member of the executive board of The Financial Post Co. warned in The Post's weekend edition. ''As a group, they have more power and influence than any other identifiable element of society.''

Around the same time, Jeffrey Simpson, in an op-ed page piece for the Globe & Mail, criticized the ''cynicism'' of the Canadian press. This is one of the corollaries to the central APM thesis of the media's mind-controlling omnipotence. Another is its monolithic leftism, especially at the CBC, a favorite scratching post of Financial Post columnists. And, as if that were not enough, there's always its reckless disregard for privacy and reputation.

The fascinating thing about this is that the most prominent and vocal alarmists about media power tend to be people in the media: they are thus permitted to stroke themselves in public over their importance, behind a veil of concern for the public interest. Most of the time, therefore, the question of what should be done about it is left uneasily unanswered, raising as it does some rather tricky further questions about press freedom, constitutional rights, career advancement and the like.

Black has no such qualms. What's needed, he says, is for owners and publishers to take a firmer hand in the newsrooms of the nation, along with the strict application of Canada's libel laws. ''Journalists, as a group, and like all other powerful groups, require some protection from themselves and their own excesses,'' he says.

I don't have a great deal of difficulty with his first prescription. Ownership of property confers the right to dispose of it as one sees fit; if a newspaper proprietor wishes to make of it his personal organ, that is his prerogative.

It is a particularly phoney interpretation of the freedom of the press that would ''protect'' journalists by state sanction from the editorial direction of their employers, as the Kent Commission recommended. For that is to suggest the public has a proprietary interest in the content of a private press, which is tantamount to nationalization.

What I take issue with is the Black-Simpson vision of journalists, especially in Canada, as some sort of mongol horde of powerful, skeptical, reckless leftists racing through society, laying waste to reputations and sacking governments at will. It is the same simple, monocausal view of human behavior that claims cigarette ads turn people into smokers, or that pornography turns men into rapists. This isn't to say that we are not easily impressionable beasts, but only that the range of factors coming to bear on our actions and perceptions is a little wider than what we see on TV or read in the press.

Those ultraslick commercials with the $48,000 Chryslers in Korea didn't do Richard Gephardt much good in his failed presidential campaign; an overwhelmingly Tory press hasn't prevented the British Labor party from governing for much of the postwar period; rape and cigarettes were around long before the mass media, and haven't diminished where the media have been suppressed; the Edsel was a flop. Need I go on?

At best, the press plays a peripheral role. It more reflects than shapes the opinions of the public. As such, its inherent political bias is not so much left or right - my leftist friends are as suspicious of a conservative conspiracy in the press as Black is of its squishy-left tendencies - as status quo.

CLUBBY LOT

Secure from competition, yet overburdened in their assignments (which does much to explain why the media is such a profitable industry in this country) Canadian journalists are by and large a comfortable, clubby lot, without much time for research or fire for inquiry. There is hence very little questioning of the basic preconceptions of Canadian political discourse.

One of these, contrary to Black's notion of the press and business as ''rivals,'' is the dominant pro-business ethos, in the sense of favoring the producer interest over those of consumers, espoused by all three parties and slavishly reprinted in the press. When an auto plant shuts, the backbenchers and the media are in uproar; when import quotas drive up the price of cars 25%, nobody says a word.

I might wish the press were as omnipotent as Black seems to think. But if I wanted to be influential, I'd rather own a newspaper than write for it.