AMERICAS WATCH, established in 1981 to monitor human rights conditions in Latin America, has been an aggressive and often savage critic of the Reagan administration's approach to human rights. The director of Americas Watch, Juan Mendez, is an Argentine lawyer who was required to leave his country in order to avoid persecution.

This volume is a collection of six essays on nine countries in Latin America written by scholars and activists. Its central thesis, unrelentingly advanced, is that "the Reagan administration has no true human rights policy." Such a situation has arisen, it is contended, because the White House is interested pmarily in implementing its basic belief that East-West rivalries should determine U.S. foreign policy. The Americas Watch thesis is endorsed in a moving preface by Jacobo Timerman.

Not surprisingly, this volume is high in decibels in its criticism of the State Department. The authors are understandably resentful of the State Department's attitude, characterized as "hostile," to non-governmental human rights groups. That resentment is especially bitter when the State Department alleges that some human rights groups support left-wing insurgents in Latin America.

Some will find that this book is one-sided and that it belittles and bullies its opponents. But others will feel that, in view of the core thesis of the book, it is not more partisan than it should be. That core thesis is that the advancement of human rights should be a central and paramount objective of U.S. foreign policy. Indeed, the policy of human rights "should be pursued even when other interests . . . suffer as a consequence." That proposition is, of course, not agreed to by all students of foreign policy, including some of the most ardent enthusiasts of human rights. But it is the firmly held and powerfully argued thesis of With Friends Like These.

THE AMBIGUITIES about human rights or even the absence of any policy on the part of the Reagan administration has led to tragic consequences on those many occasions when intervention by the White House would have been effective. One of the most effective stands for human rights was taken by Vice President George Bush when on December 11, 1983, he issued an ultimatum on human rights to the 31 top military commanders in El Salvador; as a result, death squad "killings in the first half of 1984 dropped to less than a quarter of the number in the first half of 1983." But the failure of the Reagan administration to act has led to continued and horrible abuses in Argentina, Chile, Uruguay, Peru, Colombia and four nations of Central America -- developments chronicled with an overwhelmingly cumulative effect in this book. Especially well developed is the chapter on El Salvador by Aryeh Neier, vice chairman of Americas Watch.

This study of the violation of human rights in Latin America tends to assume that past and present military alliances between the United States and the continent are undesirable. Americas Watch has a view of Latin America that is opposed to many of the policies which the United States has followed over the four generations. It rejects or does not mention considerations of national security which dominate the thinking of the present and some previous administrations. Neither does this volume make much reference to the religious and theological revolution in Latin America initiated by the pronouncements of the Catholic bishops at Medellin in 1968 and at Puebla in 1979. But With Friends Like These is nonetheless a well researched and powerful documentation of the errors, confusions, misrepresentations and untruths set forth by the Reagan administration in its treatment of human rights in Latin America.