In October 1974 , Vorster initiated a foreign policy of " Détente " seeking support for a constellation of Southern African states who would be a united front against a common enemy , communism . The use of white buffers states began to fail in 1974 with a coup in Portugal , known as the Carnation Revolution , and by 1975 black liberation groups were in control of its colonies of Angola and Mozambique . BOSS was instrumental in organizing the search for influential allies in the region and arranging the meetings . This policy was soon destroyed by the South African invasion of Angola in 1975 and in June 1976 with the Soweto riots
Soweto riots
Soweto uprising
State Security Council