Lots of chaos there right now, and note that Obama had already commented publicly on Thurs--from this background article which appears to have been ready for publication just before the above attack and the editors then inserted a graph about that:

Political Strife in South Sudan Sets Off Ethnic Violence
By Isma’il Kushkush, New York Times, Dec. 21, 2013

KHARTOUM, Sudan — He sat among tens of thousands of terrified people crammed into the United Nations compound, most of them women and children, taking notes about their desperate rush to safety. Like them, he had come seeking protection.

“They came to my house,” the man, Biel Boutros Biel, a human rights activist, said of the South Sudanese security forces. “I knew they were coming after me.”

After President Salva Kiir announced that his government had headed off a coup attempt by his former vice president last week, South Sudan was tossed into uncertainty and upheaval. Hundreds are believed to have been killed in the capital, Juba, with thousands more fleeing into the bush to escape the violence [....]

“Today, that future is at risk,” President Obama said in a statement on Thursday. “South Sudan stands at the precipice. Recent fighting threatens to plunge South Sudan back into the dark days of its past.”

Events are unfolding fast. United States aircraft sent to evacuate Americans came under fire on Saturday, wounding four soldiers. Rebels are believed to have taken control of some of the country’s oil fields and alliances are shifting.

Like many conflicts in this tenuous nation, the fighting has taken on an ethnic dimension, human rights workers say. [....]

How Hollywood cloaked South Sudan in celebrity and fell for the 'big lie'

Film stars have been speaking from a flawed script about the newest nation. Daniel Howden points a finger at those who have failed to grasp the awful reality

The Observer, 28 Dec., 2013