Energy blackmail and unethical foreign policies
Bechuanaland, later Botswana, had eight principal tribes prior to independence. The king of the Bangwato, and later to become the first president of Botswana, Seretse Khama, travelled to England after WWII to study law, prior to taking up the leadership of his people. While there he married Ruth Williams, a clerk at Lloyds of London, in 1948, the same year that South Africa introduced apartheid.
South Africa’s policies were predicated on a black man not being allowed to touch a white woman, and they feared a royal mixed marriage across the border would threaten stability in the area. South Africa therefore placed pressure on Britain in a very modern way: it threatened to deny Britain access to energy, specifically uranium that the UK needed to develop its nuclear programme. To its shame Britain conceded, and Ruth and Seretse were exiled in Britain for six years.
Energy security doesn't just mean our supplies of energy can't be cut off or attacked by those outside our borders: it also means we don't have to collude with shameful regimes to keep our lights on.
(Picture courtesy of 'Colour bar' by Susan Williams ISBN 9780141026138)