Since independence, the MPLA-PT government had faced several internal opponents and rivals for power. Broadly speaking, one can distinguish between antigovernment and antiregime opposition groups. These groups differed in their goals, methods, and bases of support. On the one hand, antigovernment groups protested or sought to change the incumbent leadership, used conventional means of political opposition ranging from passive resistance to attempted coups, and drew support from constituencies almost entirely within the country. The main source of such political opposition was factionalism within the MPLA-PT. Clandestine opposition groups and religious sects also contributed to antigovernment tensions (see Political Opposition , ch. 4).

On the other hand, antiregime groups sought to transform the political system or overthrow the ruling MPLA-PT, resorted to efforts at secession and armed rebellion, and received substantial external support. The most prominent of these political opponents were FLEC, the FNLA, and UNITA. Whereas the first two had become spent forces by the 1980s, UNITA continued to pose a serious national security challenge.

The MPLA-PT government survived this host of threats by developing an extensive internal security apparatus to supplement the armed forces. This system consisted of a paramilitary territorial militia a state security ministry with penal functions, political police, and border guards a national police force and a nationwide popular vigilance brigade organization.

Data as of February 1989