 Complete the following phrase:  The South African Border War was closely linked to the Angolan Civil War. South African expeditionary units had openly invaded Angola in 1975 during Operation Savannah, an ill-fated attempt to support two rival Angolan factions, the National Union for the Total Independence of Angola UNITA and the National Liberation Front of Angola FNLA, during the civil war. The SADF was forced to withdraw under overwhelming pressure from 