In the early morning hours of June 14, the integrity of the nation of Botswana was violated by the South African government. A dozen people were killed and more wounded by members of the South African Defense Force. Most victims were South African citizens. One week later the U.N. Security Council voted unanimously to condemn South Africa's act of aggression against this small, poor and nearly defenseless country.

For nearly 19 years of independence, Botswana has successfully struggled to maintain a nonracial, multiparty democracy in a region of violence and racism. Numerous reports by U.S. agencies and independent investigators over many years have found Botswana to have the best human rights record in Africa. No political prisoners, freedom of expression for al and open elections every five years are some manifestations of this effort.

An article of Botswana's faith has been that, by showing that genuine nonracial democracy could thrive in southern Africa, Botswana might make a contribution to peace in the region despite its small population (about 1 million) and meager resources.

World Bank data show Botswana has achieved the best overall economic record in Africa in the past two decades. Botswana has shown that development and democracy can go together, that foreign investment can be welcomed and human rights respected.

Botswana also has provided a refuge for individuals of all races fleeing political persecution: from South Africa, from southern Rhodesia under the Smith regime, from Zimbabwe, Angola, Namibia and Lesotho. The rules have been clear from the beginning: Botswana will provide refuge, but will not permit refugees to engage in any military action against their country of origin. Refugees who will not play by these rules are deported or, if convicted after public trial, jailed.

The countries in the region, including South Africa, know the facts; they have known them for nearly two decades. The Western democracies, including the United States, know them as well. Since Botswana is an open and democratic society and people are free to travel throughout the country, verification is an easy matter for anyone interested. Why, then, an invasion? Why this assault on a decent and innocent country?

Apparently South Africa believes it has the right to cross borders in order to kill or capture people who think South African society is unjust, and that it has the right to define who is or is not a threat to the South African government. If a neighboring country refuses to return or expel South African citizens, South Africa claims the right to act on its own.

This is not a doctrine of hot pursuit; it is an attempt to force sovereign countries to be extensions of the South African government. If Cuban troops landed in Florida and killed refugees opposed to Castro, Americans would be outraged. The South African operation was an exact parallel.

In the past few weeks we have again been painfully aware of acts of terrorism and of the limitations of expensive national defense. But in the case of the attack on Botswana, the terrorism was official policy of the South African government.

Botswana needs our help. We should make U.S. support for Botswana crystal clear as that nation attempts to defend its integrity. Our vote in the United Nations was a small step toward that end.