The United States wants to boost trade with Africa as the region\'s economy grows despite the global financial crisis, US Secretary of State Hillary Clinton said Monday. \"Looking across Africa, we see enormous economic growth even as the global economy continues to struggle. Seven of the world\'s 10 fastest-growing economies are in this region,\" Clinton told a gathering of American and South African business leaders in Johannesburg. \"These emerging markets present enormous opportunity for American trade and investment.\" South Africa is the largest US trade partner in the region at $22 billion (18 billion euros) annual trade between them, she added. \"Over the next two decades, South Africa will be making big investments in infrastructure, which will create massive new opportunities for American businesses in energy, transportation, and communications technology. That will mean more jobs for South Africans, and more jobs back home.\" She spoke after returning from Nelson Mandela\'s rural homestead in the village of Qunu, where she held a private lunch with the Nobel Peace Prize winner who led the struggle against white-minority rule in South Africa.