Calling columnist-commentator James J. Kilpatrick a conservative is an understatement roughly equivalent to announcing that Tip O'Neill may, in fact, know how to handle a gavel. Kilpatrick's attacks of conservatism (those punctuated with "horsefeathers") can be so intense that, by comparison, the late and the Honorable Pepin the Short would look like a co-chair of the California delegation to Madison Square Garden.

So when Kilpatrick reveals, as he did into a working microphone last Tuesday night, that Ted Kennedy's categorically liberal speech and the crowd's response to it had combined to produce "one of the great moments I've ever experienced in 15 conventions," then chances are pretty good something special has happened.

Those of us who had questioned why Kennedy remained in the race long after any realistic chance of winning was gone had to wait all of two sentences and three ovations in the Garden for a full explanation. Kennedy, after some nine months of chasing, had found the shared podium that had eluded him. It had almost been worth all the frustration.

Last fall, the Massachusetts Democrat had been on prime time and, through the dullness of his performance, had blown that opportunity and maybe even a good part of his candidacy. That was the night when Roger Mudd, in a series of not-to-be-unexpected questions, elicited from Kennedy answers that made him sound about as articulate as your average unranked veteran middleweight.

But in New York, it was Ted Kennedy's turn, maybe his very first turn, to establish standards rather than to be measured by them. Make no mistake about it: he has been the direct beneficiary of close identification with his late brothers in people's minds, particularly in the minds of those people who regard them as martyrs. The brothers symbolized happier times when our national confidence and our native optimism had not yet run short.

But Ted Kennedy, in the Mudd interview and beyond, was being compared with the romanticized and unrealistic reminiscences of John and Robert. The consensus soon became that he lacked the wit and eloquence of his brother the president and possessed neither the passion nor the commitment of his brother the attorney general. Polls of primary voters disclosed that some Democrats resented the Youngest Brother, that they expressed almost a sense of betrayal for his tarnishing of the legend by his being fallible. Almost certainly the shrewd Bob Strauss, chief of the Carter-Mondale campaign, had that voter attitude in mind when, last winter, he needled the Kennedys that "Rose didn't have any triplets."

But last Tuesday night in the Main Event at Madison Square Garden, it was Edward Kennedy's chance to deliver a more subtle and more devastating needle to his rivals, particularly to the president of the United States. He more than made the most of it. He could and did set a standard of performance and of eloquence that Jimmy Carter could not meet, both for strategic and personal reasons.

In a convention overflowing with the non-negotiable demands of single-interest lobbies -- very few of which had been discouraged by the senator -- Kennedy reminded the Democrats of their party's history and of their obligations "to speak for those who have no voice and to remember those who are forgotten."

Still no word from the Marshal McLuhan scholars in our neighborhood. We had been persuaded, you will recall, that Teddy was too "hot" to be an effective communicator via television. To communicate effectively, one has to be "cool." Kennedy, in the Garden, was anything but cool, but he was totally effective. Maybe the convention context explains the viewers' favorable reaction to the Kennedy speech, which in practically any Democrats' judgment was a lot easier to listen to in August than to run on in November.

Give Jimmy Carter credit for understanding what was happening to what had been, up to then, his convention. From the moment of the speech onward, the Carter people appeared seized by a single objective: to get Kennedy on the same spot with Carter on Thursday night. They were almost willing to trade the party platform for a platform picture. After ducking Kennedy for eight months, the Carter people were now panting after him. He had set the standard that could not be met. He had salvaged a failed campaign in an hour. sHe had his revenge. On Thursday night, he made only the minimum deposit required while the president openly pursued him through the crowd on the platform -- and on national television.

The rule from earlier Kennedy campaigns was "Don't get mad, get even." In Madison Square Garden, Edward Kennedy seemed to be trying to do both. It didn't become him or the president. Thursday was an evening that, politically, helped both men very little and the Democratic Party even less.