WHEN COLE Porter wrote "But in the Morning, No," he wasn't talking about television. But he might have been. The British consider TV at breakfast to be vulgar and uncivilized, and to judge from the current unkempt warfare between "Today" and "Good Morning America," those Brits may be right.

On the surface, they are news-service programs (both outclassed by the low-rated "Morning" on CBS.) But behind the scenes, which is usually where the real fun hides, there are more rivalries, intrigues, accusations, jealousies and tattletales than on "General Hospital" and "The Young and the Restless" put together.

For years early morning television was a peaceful gold mine, the monopolistic province of NBC, where Sylvester "Pat" Weaver had invented "Today" in 1952, staffing it with a jazz buff and a monkey. The monkey was J. Fred Muggs and the jazz buff was an inimitable, ingenious, ingratiating interlocutor named Dave Garroway. The program went through various phases over the years and its competition at one point included Walter Cronkite teamed with a lion puppet named Charlemagne.

But there was never a serious challenge to its dominance until 1975, when ABC unveiled "Good Morning, America" and began eating into "Today's" ratings like a kid scarfing down Screaming Yellow Zonkers. This year, "GMA" has begun to overtake the king of the hill in early-morning Nielsens; a typical recent week saw "GMA" score a 5.1, "Today" a 4.9, and the one-hour CBS News "Morning" show a 2.3. But in the past five weeks, "Today" has made a comeback -- beating "GMA" twice and tying it twice for first place. This has had the effect of heating up the conflict even more.

While "GMA's" audiences are up 31 percent from last year, "Today" has only registered gains of 5 percent, and "Morning" of 15 percent. The surprising thing is that "GMA" has lured new audiences to early-morning television; everybody's ratings are up, but "GMA" is getting the largest share of those viewing.

Early morning is one of the few times periods in television yet to be fully developed to a competitive level of peak hysteria. Even with viewing levels up, the networks still can only lure about 14 percent of the available national audience to their shows. America continues to rely more on radio for its morning media feed. But "GMA" executive producer George Merlis notes that his show has attracted 4 or 5 million people who weren't watching morning TV before and says, "I think we can double the early morning audience from what it is now" within the next five years. Viewing and working patterns are changing in the country, the available audience will grow larger, and the portability of TV sets is always increasing.

And so the morning wars are on -- bombs bursting on air by the dawn's early light. The strategy currently being employed by Steve Friedman, the aggressive, young "Today" executive producer, is to imitate "GMA" as much as possible while deprecating "GMA" as often as possible. Friedman's been bending more ears than Marc Antony with tales not only of how awful and corny "GMA" is, but also how disgruntled some of its production staff allegedly has become.

"Literally not a week goes by that I don't get a resume from somebody at 'Good Morning, America' looking for a job with us," says Friedman. "They're very unhappy over there." He also says longtime kingpin "Today" continues to "outbook" ABC's show with newsier, hotter guests and interviewees.

Merlis says the idea that "Today" regularly scoops his show is, well, bovine excrement. And as for his staff's morale, "The resumes are flooding into this place, not out of it."

"We are totally beating and outbooking 'Today' on news guests and celebrities," says another GMA spokesman.

Sometimes this fight gets so messy it makes the presidential campaign look dignified by comparison. And it comes complete with defectors. Rona Barrett, the Betty Boopish gossip columnist, recently abandoned "GMA" for NBC, "Today," and a slot on the revamped "Tomorrow" show. Now, says the "GMA" spokesman, "We keep seeing items planted in newspapers by Friedman, and we think his source is a discontented Rona Barrett."

In the competitive climate, stories run wild, including the allegation that David Hartman, "GMA's" potato-faced host, has turned into a prima donna. "Hartman even has approval over the graphics they use," Friedman claims. He and others believe that Hartman was involved in Sandy Hill's removal from her position.

Merlis says it is "not so, absolutely not so" that Hartman has approval over graphics. He says Sandy Hill (who succeeded Nancy Dussault in the copilot chair now occupied by Joan Lunden) is still on the show occasionally as a feature reporter. But an insider at GMA concedes Hartman and Hill suffered from a "personality clash" that couldn't have contributed to her longevity.

As for Hartman ruling the roost, Merlis says, "David has a lot of control, a good deal of input" and that Hartman "is on the phone 15 times a day with suggestions," few of which get used. Of Hartman's reputation as a tyrant, one ABC source says in not-so-convincing defense, "Tell me anyone in television of that stature who isn't that way" and, "David is basically a nice guy."

But Mr. Nice Guy does have his territorial rights. Asked if Lunden will at last prove a "cohost" tolerable to Hartman, an ABC News source meticulously points out that "Joan is not technically the 'cohost.' There is one host, and that's David. It is semantically incorrect to call David a cohost. The show was designed from the outset and built around him."

Well excuuuuuuse me!

Frequent tales of feuding between Hartman and Steve Bell, the ABC News anchorman on the show ("GMA," unlike its competitors, is produced by the entertainment division, not the news department) are being scotched left and right by GMA spokesmen. "They visit each other's families at Christmas time -- it's that sort of thing," one gushes.

Hartman likes doing news interviews, at which he often proves embarrassingly awkward. Merlis is asked how Hartman, who wasn't even a very good actor, comes across as a journalist. "I don't think he pretends to be," says Merlis. "He's a communicator."

"Communicator" was just the term Weave used for Garroway lo these 28 years ago.

If "GMA" has its personnel problems, "Today" isn't exactly Happy Valley. For years, cohosts -- or whatever the heck they are -- Tom Brokaw and Jane Pauley have been said to be backstage warriors. Here the stories are supported by what appears on the air: Two people who seem to feel as warm and toasty toward one another as George and Martha in "Who's Afraid of Virginia Woolf?"

Producer Friedman insists they are really pals, but virtually all the remodeling he's doing on the show is designed to warm it up. He acknowledges that it got too dull and stuffy and was being produced only for the audience in New York and Washington. He is trying to develop a "family" of regulars and contributors a la GMA and has brought in such iridescent luminaries as the one-and-a-half-and-only Willard Scott, former Washington radio Joy Boy and longtime WRC-TV weatherman extraordinaire.

In a recent tirade against the decling stature of "Today," New Yorker TV critic Michael J. Arlen hooted at Willard for being a "noisy, unfunny, phony-grass-roots" character. But as his ever-growing legion of fans can probably perceive, Willard is about as phony as an April shower. He's a cured-again ham whose contribution to "Today" has been rejuvenating and therapeutic, and he now draws the show's biggest share of fan mail, after an initial, and mystifying, torrent of hate mail upon his debut.

A few other churlish gnomes have chided Willard in print for being the new '80s version of J. Fred Muggs. But Willard, self-effacing to a fault, actually made that comparison himself -- jokingly of course -- at the very moment when his ascent to "Today" was announced.

The plot to warm up "Today" thickened last summer when actress Mariette (Polaroid) Hartley was brought in as a vacation substitute and, rumors said, possible replacement for the cold-shoulderish Pauley. But Hartley subsequently boo-hooed to the press about how snobbish and mean those NBC News types were to her and how she thus had to turn down NBC President Fred Silverman's offer of the moon and several large meteors.

Friedman says Silverman has assured him he never made Hartley a concrete offer and says that while people got along well enough with Hartley, they couldn't stand her manager.

Friedman has other woes. Brokaw, whose official nickname on the set is Duncan the Wonder Horse (it has to do with his being intrepid, or something) has been noticeably restless about leaving "Today" and perhaps NBC, now that mopey Roger Mudd is expected to move into the John Chancellor Chair of Nightly News anchordom.

Then there was the loud Silverman grump to a reporter about how "Today" looked like a "mausoleum" He meant the set, not the cast. Naturally "Today" has commissioned a new set, which Friedman swears will not be a copy of that fake living room used by the King David version on ABC and which will be unveiled in the next few weeks. Friedman would like to move the show down to the first floor at Rockefeller Center, where it began, and that would enable Willard to do some of his weather reports from outdoors.

As for the impending arrival of the rather ridiculous Miss Rona, Friedman insists this doesn't mean "Today" is whittling away at its own dignity. "Rona Barrett is every bit as good at her kind of reporting as Marvin Kalb is at his," Friedman says with a fairly straigt face.

He says, in effect, that no matter how low "Today" sinks, it won't ever get into the basement with GMA, which he considers a trivial grab bag of household hints. He cracked to one reporter that he didn't think GMA viewers needed to be told an umteenth time how to fix a doorknob.

This charge, at least, brings out some wrath in the otherwise unflappable Merlis. Handyman regular Al Ubell "doesn't fix a doorknob every week," Merlis says. "But if you don't think that's important information to the audience at home, then you're looking down your nose at them. That's a very elitist attitude. I want to know how to save $200 on my fuel bill this winter! I want to know how to protect my shoes from the ice and snow! I don't think it's beneath the dignity of the television medium to give people useful information".

Merlis says he has gleaned such valuable insights from GMA regulars as the wisdom of keeping Saran Wrap in the freezer so it doesn't stick together. And that you should keep popcorn in the freezer because if you do, "every kernel pops."

For all the popcorn in the freezer, Merlis rejects the charge that GMA is a "soft" show, says he just uses "more service material," that "in hard news, we're just as competive" as "Today" and that demographics show the GMA audience is not composed of dummies but is "younger, richer, and better educated" than NBC's. He also notes from reading rundowns of each day's "Today" show that Friedman does seem to be copying the show he loves to defame. "I guess they've learned a few things," says Merlis.

"I don't think there's a feud going on," he says. "Steve and I send each other funny notes. I sent him one that said, 'repent, repent, repent.' I meant to say, 'atone.'

But the way to handle a tough thing is to do your own best show. They're going after our audience, which I think is stupid. If I were them, I'd go after the 85 percent of the country that doesn't watch any early-morning television".

However, it could be that 85 percent of the country would be happier and healthier if just left alone.