THE EDITORIAL will be brief. It will also be in the nature of a memo. We address it to President and Mrs. Carter, the White House staff, the Washington-based media and the public. That includes practically everyone in the immediate region, you will note - including ourselves and also those who like to gawk at the political high life that is attracted to our city. The subject of our memo is Amy Carter. The message is simply this: For God's sake, let us leave this child alone, let us not convert her into a public relations commodity.

Our feelings on this subject were provoked by those arresting photographs of the past few days, which seemed to capture a forlorn child going through the paces of her father's inauguration and her own first day at local public school. Somehow, suddenly, nine-year-old Amy Carter seemed to have been transformed from a lively, normal unaffected little girl into a baffled and beleaguered public figure. It seemed mindless and cruel. We are not casting doubt on her resiliency or capacity to withstand the pushing, prodding, noisy attention. We are questioning its wisdom, value and humaneness.

Before you say it, we will: Yes, it is true that this newspaper has dogged Amy Carter along with the rest. And yes, it is true, that the Carter family has seemed willing to let the nine-year-old Amy get her fair share of celebrity - and has even invited much of the public note. But that celebrity can quickly tear away from their control, and there are a few things about the consequent mob scenes worth noting.One is that Amy Carter, unlike earlier tiny tots or teenagers at the White House, is at a particularly vulnerable stage of her life to endure the heavy, intrusive attention. Another is that this unrelenting attention works precisely to negate the healthy aspects of her attending public school.

On NBC news Monday night, John Chancellor closed the network's coverage of Amy's first day at school with sound and reassuring words: ". . . as far as we're concerned, that's the last you'll see of Amy Carter at school on this program. We wish her well in her studies, and we respect her right to privacy." It would be good if the rest of us took the same pledge. President Carter is being widely hailed these days for helping restore a long lost element of "normality" to our public life. How odd it would be, and how sad, if his nine-year-old daughter were to be the one person excluded from its general benefits.