ALLISON AUBREY, HOST:

We wanted to learn a bit more about the conflict in South Sudan, so we reached Cameron Hudson. He's the director of the Simon-Skjodt Center for the Prevention of Genocide at the United States Holocaust Memorial Museum. He previously served as President Obama's special envoy to Sudan during the country's partition. And I asked him why there is so much urgency to get something done now.

CAMERON HUDSON: The situation that's been boiling for a number of years is really at a crisis point. The word genocide, I think, is not hyperbolic in this situation. It's been very clear for a number of months that both sides have been arming themselves. They've been increasingly using hate speech and other dehumanizing speech on the radio and other, kind of, public media. And so we've seen a lot of the kind of early warning signs within society, not to mention hundreds of thousands of people flowing out of South Sudan, mostly, I would say, women and children, which is a very concerning sign that the men are staying behind expecting that there's going to be a fight.

So I think that we're really at a crisis moment here. And certainly if the people on the ground think that we're not paying attention and that there won't be consequences for the actions, I think Samantha is rightly very worried that we could face a genocide on our watch.

AUBREY: Can you give us a sense of what's fueling the violence there?

HUDSON: So it's really a conflict that is ethnically based but has spilled over into the political arena, where we have the president of the country, Salva Kiir, who is an ethnic Dinka, which is the majority tribe in South Sudan and his former vice president, Riek Machar, who represents the Nuer faction, which is the largest minority tribe in the country. There has often been conflict between the Dinka and Nuer going back centuries, really, because of different roles in society. And so that has spilled over into, you know, sort of open warfare in the streets between these two tribes and two political parties.

AUBREY: Now, in 2011, when South Sudan seceded from Sudan, there were really high hopes that creating a separate state would help solve some of the problems that led to the violence. But here we are three years later. Is there anything you think could have been done differently - from the beginning - to head off what we're seeing today?

HUDSON: I think we have to take a sort of longer look at the history of South Sudan because South Sudan is independent today because it fought, essentially, a 30-year civil war with Sudan, the country that it seceded from. So it was a real achievement to end that civil war. It just so happened though - and I think a lot of U.S. negotiators, myself included, miss the fact that the unifying theme within South Sudan for many of these years was their hatred of the North.

AUBREY: And now they're all coming out?

HUDSON: And now that they don't have that common enemy, you're seeing them turn on each other. So while preventing and ending one war, we planted the seeds for this new civil conflict to happen.

AUBREY: Do you think that any diplomatic action can make a difference at this point? We've heard about arms embargoes or economic sanctions - of course, those can take a while to be effective. Do you think any of these things can make a difference?

HUDSON: I think that we have to try. Even if we don't know if they're going to make a difference, we have to try. We have to be on the right side of history. I would say that the South Sudanese have done everything that they can to isolate themselves. The leadership of the country has cut itself off from outside political intervention. It's not talking to previous friends and allies. It's not taking advice from outsiders. So they're making it very, very difficult for diplomacy to work.

AUBREY: This situation has been compared to Rwanda where, you know, arguably, we waited too long to act. Why do you think all of the urgent calls to intervene are coming now?

HUDSON: Well, I think that we're at a crisis moment and we recognize that once violence erupts in a whole-scale way, it's going to be very, very difficult to put it back into the bottle. And so if we don't act now to take preventive action, then it's going to scale up so quickly that it will be virtually impossible going forward to put it back under control until there's a winner. And we saw in Rwanda, it took 100 days for that genocide to be carried out. So once these things scale up, they do so at an explosive rate that's really difficult to intervene once that's happened.

AUBREY: Cameron Hudson, director of the Simon-Skjodt Center for the Prevention of Genocide at the United States Holocaust Memorial Museum.

Thank you so much for joining us and for shedding light on this sobering topic.

HUDSON: Thank you.

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