(CNN) -- There are certain moments of parental pride you know are coming: their first words, first steps, first date. And then there are the ones that blindside you. Like this: The night before the Nelson Mandela memorial service, my 13-year-old son said, "Dad, I'm going to wake up at 4 to watch the Mandela memorial." I was so proud that he was so inspired. He's an all-star basketball player who mainlines ESPN. Now he wanted to get up in the middle of the night to watch CNN. Great success. And when President Obama spoke for our nation, I was grateful we'd heard his remarks live. Obama captured President Mandela's remarkable capacity to awaken activism. Across oceans, across continents, across racial divides, across generations, Mandela sparked what Robert F. Kennedy described to the South African people as "ripples of hope."
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President Obama shook hands with Cuban leader Raul Castro at Mandela's memorial
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Paul Begala: Like Reagan shaking Gorbachev's hands, Obama's act makes sense
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He says even a simple handshake can be potent and transformative
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Begala: It sends out a ripple of hope from the right side of history
I believe Obama shook Raul Castro's hand for the same reason Reagan shook Gorbachev's or @placeholder shook that of F.W.