What were they defending it against?
The Communist menace, that's what.
One of the first repressive laws they passed was the Suppression of Communism Act (Act 44 of 1950).
The National Party in South Africa and the Communist Party in Russia fell from power a couple of decades ago. The National Party has since disappeared from the scene, its remnants being absorbed into the DA and the ANC, which are now the two biggest parties in the South African parliament.
The Russian Communist Party, however, still exists, and look what they're up to now:
В Госдуме создают депутатскую группу по защите христианских ценностей - говорят, что для пропаганды : Новости : Накануне.RU, which, being interpreted means
And here it is, from the horse's mouth:
We intend to develop international cooperation for the common defense of Christian values, because we believe that the future of Europe, as well as the future of a revived Russian Federation does not conclude in a plantation of permissiveness, of total consumption, dehumanization, flouting the basic norms of human common life, and a return to traditional, orthodox Christian values.
That's from Sergei Gavrilov, a Communist Party representative in the Russian Duma.
Sergei Chapnin, an Orthodox journalist in Russia, comments on Facebook:
What a disgrace for Russia! What a mockery of history! The Communists are going to defend Christian values, "the Communist Party Guide never took anti-Christian positions. You can not put the Communists in the current blame the sins of 20s, the acts of" militant atheists "Yaroslavl-Gubelman or the latest large-scale" Khrushchev's "persecution of the church in the early 60's" (S. Gavrilov, the Communist Party).
One doesn't know whether to laugh of cry.