THE LOGIC behind the world summit for children, which is to be held this weekend at the United Nations in New York, is impeccable. The young lack a voice and vote in the great affairs of the world and must depend on the favor of others to get a fair share of their nations' attention and resources. The results are evident in the statistics gotten up by UNICEF, the U.N. children's agency, which is organizing this giant meeting of world leaders. In the developing countries tens of thousands of children under the age of 5 die every day. These are in the main preventable deaths; the economic and technological resources to prevent them are available. So far, however, the political will to bring them to bear is not. Summoning it up is the purpose of the summit for children.

One current of the thinking behind this conference is that with the easing of international tensions a great peace dividend exists that can be applied to the world's unmet social needs. It is pointed out that developing countries now devote fully half their means to arms and service of debt. What is striking about the summit's agenda, however, is not the grand size of its claims on public funds but the modesty. For just a few billion dollars worldwide, immense gains could be made in the health of pregnant and newly delivered women and of their infants and young children. Immunization, for example, is easy, safe, effective and cheap, and could save thousands of lives a day. Diarrhea, which is said to cause 2.5 million deaths a year, can be prevented by a 10-cent package of oral rehydration salts. Provision of basic nutritional information can cut deeply into malnutrition. No technological breakthrough is required to prevent hundreds of thousands of annual maternal deaths -- just simple care. This is the message that many world leaders need to take home from the summit.

President Bush, who will be in New York, has his own message to take home. The child advocacy groups are using the summit to draw attention to the woeful American performance in some areas of child health. Child mortality rates, for example, are a scandal. In the United States tens of thousands of youngsters under the age of 1 still die every year, while perhaps 100,000 survive disabled, another 100,000 are homeless and a quarter of the child population misses out on immunization. As Americans contemplate the grim situation of many children in the Third World, there is no room for complacency at home.