Now they've done it. Those Carter people think that the White House is theirs, just because they won it fair and square, and that they can trample over the traditions of the real Wasington, which is people from defunct administrations.

They've committed all kinds of outrages, such as selecting their own favorite restaurants or even their friends. But now they've gone too far.

They have gotten Amy Carter a hermit crab for a pet.

Only he politically naive would question who "they" might be, or advancethe simple argument that the crab was a chance Christmas gift from a friend. But that's like suggesting that the concept of "Amy Carter" is not a political entity, to be used for image and symbolic purposes, and is, instead, say, a little girl.

Just as every President needs a gracious wife, that is to say one which is more presentable than he is; an irresponsible brother and a loveble daughter, for the sake of rounding out and softening the image, every President needs a family pet.

But it cannot be hermit crab.

Presidents have dogs. Even a cat is risky - cats can be arrogant, and they have their enemies. Birds, hamsters and cheetahs are out of the question. The dog is the lowest common demoninator in the pets-as-symbols business, and just about every President has recognized that fact. Some have had many dogs; there are always politicans who overdo everything. A few have omitted having a dog , although not in recent history.

But a hermit crab? A thing with a hard shell that walks sideways?

It has been said that crabs are really soft and sweet inside. Thereare even seasons when they are soft and sweet on the outside. It doesn't matter.There is no way on earth that a crab can be projected as being faithful, warm, cuddly and lovable, which are the job requirements for a presidential pet.

Amy Carter is just going to have to try again. If she wants to help Daddy in his career, she will just have to hand that crab over to the chef and learn to love mongrel puppies.