IN recent weeks South African combat troops were once again hunting down SWAPO guerrillas inside Angola: the first such cross-border strikes since Pretoria withdrew its occupying forces from southern Angola in April. This latest action was only one of several aggressive moves by the Botha government recently. In mid-June, South African commandos attacked suspected African National Congress targets in Botswana's capital, Gaberone. A few weeks earlier a South African demolition team was caught attempting to blow up a US-owned oil installation in Angola's far northern province, 800 miles above the Namibian border.
These actions are a slap at the Reagan administration, which has been trying to prod Mr. Botha into a less belligerent stance toward its neighbors. Coming at a time of growing US congressional clamor for sanctions against Pretoria, South Africa's latest salvos leave the policy of ``constructive engagement'' dead in the water. Why antagonize the United States? Why now?
The resurgence of South African militancy reflects concerns far more vital than the state of relations with the US. The driving issues are rooted in South African domestic politics. Most important, the government must demonstrate that it is tough in the face of outside provocation, particularly guerrilla activities. Neutralizing the guerrilla threat commands the highest priority of the Botha administration. Its strategy must be seen to be working. This becomes even more important in times of internal po litical upheaval, like that which has been going on in South Africa's black townships for almost a year. President Botha has come under continuing fire from right-wing parties for his political reforms at home; he cannot afford to be seen as ``soft'' toward black opposition at home or guerrilla attacks from outside.
South African whites held high hopes that the 1984 security accord with Mozambique would put an end to ANC sabotage inside South Africa, and that the cease-fire with Angola last year would cripple South-West Africa People's Organization (SWAPO) operations in Namibia. Yet attacks by both have continued. The longer they go unchecked, the greater the impact on white morale, and the louder the message to South African blacks that guerrilla warfare offers an effective weapon against the apartheid regime. The
government does not want to see this proposition win broad acceptance.