Peter Taylor reports from within South Africa on the black opposition - an opposition which is becoming increasingly frustrated and violent. The thousands of Soweto youths who left the country after the riots in the black township five years ago are now returning secretly, fully trained, with arms and explosives. Every week the list of sabotage and machine-gun attacks grows rapidly. The white South African government is now facing an increasingly successful, but as yet unreported, guerrilla war. For the first time the people who are at war inside South Africa talk to Panorama. Do they have any chance of defeating the most powerful military machine in Africa? What will be the political consequences of a war which both whites and blacks swear they will fight ' to the last drop of blood '.