President Obama's Bittersweet Arrival in South Africa

And next we want to take you overseas to south africa, nelson mandela, the 94-year-old freedom fighter in a hospital as president obama, a man inspired by mandela has just landed nearby. Abc's chief... See More

And next we want to take you overseas to south africa, nelson mandela, the 94-year-old freedom fighter in a hospital as president obama, a man inspired by mandela has just landed nearby. Abc's chief white house correspondent, jonathan karl, traveling with the president tonight. Reporter: For president obama, a bittersweet arrival in south africa, an historic first, an african american president warmly greeted where apartheid once ruled. Nelson mandela is the man who inspired a teenage obama to make his very first political speech. A few years ago, he taped a tribute for mandela's 90th birthday. Happy birthday, nelson mandela. I hope I have a chance to see you soon. Reporter: That chance may never come. Mandela's health so precarious the white house considered cancelling the trip out of respect for the family. On his way here, president obama told reporters he doesn't need a photo-op with mandela, and that it will be entirely up to the mandela whether he has one last chance to see his personal hero. This is the one known photograph of mandela and obama, a snapshot of a ten-minute meeting the two had in 2005, when obama was just a junior senator. The president has the photo on a table outside the oval office, an inspiration he sees every day he is in the white house. Jonathan karl, abc news, johannesburg.