When the National Party first came to power in 1924, Malan became minister of internal affairs, education, and public health. However, he refused to follow the leader of the National Party into a merger with the South African Party, and in 1934 he took the lead in creating a new "purified" National Party, which won the 1948 general election on a platform that included apartheid, a comprehensive system of rigid racial segregation.
Malan, a strong anticommunist, became prime minister in May 1948 and took advantage of the Cold War fears of South Africa's Western allies, none of whom came out strongly against the new apartheid policies that his government introduced. In 1950 Malan's government pushed through parliament the wide-ranging Suppression of Communism Act, which was to be used to suppress opposition to apartheid. Before the act became law, the Communist Party of South Africa had dissolved itself, to emerge some years later as the underground South African Communist Party.
Although the apartheid laws embarrassed many Western nations, Britain and the United States nevertheless saw South Africa under Malan as a relatively strong state friendly to the West. In addition, the West took advantage of South Africa's bountiful natural resources, most notably its supply of uranium, and realized that the country occupied a strategic position on the sea route around the African continent. In the Cold War context, therefore, the leading Western powers tolerated South Africa's apartheid regime because of its geopolitical importance.
Malan left office and retired from politics in November 1956. He died in Stellenbosch on 7 February 1959.
Borstelmann, Thomas. Apartheid's Reluctant Uncle: The United States and Southern Africa in the Early Cold War. New York: Oxford University Press, 1993.; Giliomee, Hermann. The Afrikaners: A Biography of a People. London: Hurst, 2003.