In this image from TV, US President Barack Obama shakes hands with Cuban President Raul Castro at the FNB Stadium in Soweto, South Africa, in the rain for a memorial service for former South African President Nelson Mandela, Tuesday Dec. 10, 2013. The handshake between the leaders of the two Cold War enemies came during a ceremony that's focused on Mandela's legacy of reconciliation.

SABC Pool / AP

In this image from TV, US President Barack Obama shakes hands with Cuban President Raul Castro at the FNB Stadium in Soweto, South Africa, in the rain for a memorial service for former South African President Nelson Mandela, Tuesday Dec. 10, 2013. The handshake between the leaders of the two Cold War enemies came during a ceremony that's focused on Mandela's legacy of reconciliation.