Rep. Frank R. Wolf (R-Va.) is one of the leading congressional experts on Sudan and has traveled to the region six times since 1989.

Will America help save a nation it helped birth? Or will it be said that a nation was born and perished on President Obama’s watch?

With South Sudan racked by violence that has displaced thousands and prompted rumors of mass graves, many people who have spent years working on this issue, myself included, are grieved at the prospect of a country at the brink of catastrophic war — not simply because of the human suffering it represents but because of the unfulfilled promise that is South Sudan.

I first visited Sudan in 1989, years before Darfur became a household word, and I have prayed for the day when the people of that long-suffering land would enjoy peace and representative government.

While I did not support Obama’s candidacy, I was heartened by his rhetoric on Sudan during the 2008 campaign . I took further encouragement from some of the individuals who joined his foreign policy team — staffers with strong human rights credentials and a stated desire to see the United States lead the prevention of crimes against humanity and other atrocities.

I fear that trust was misplaced.

The post of special envoy to Sudan remained vacant for months during crucial periods, including the final days of the implementation of the Comprehensive Peace Agreement, which ended the decades-long war between Sudan’s largely Arab, Muslim North and the mostly Christian, animist, African South. The post was empty again through most of 2013, even as the newly independent South Sudan was trying to find its footing. And when envoys have been appointed, they have had little to no entree to the White House or real influence within the State Department bureaucracy.

Meanwhile, the administration has promoted a confused and at times deeply flawed Sudan policy.

It has failed to isolate Sudanese President Omar Hassan al-Bashir, an internationally indicted war criminal desperate to maintain power, who has met widespread protests with brutal crackdowns on civil society, arrests, detention and torture. Because of Bashir, the genocide in Darfur still simmers, and violence and starvation in the Nuba Mountains are daily realities.

The Obama administration has done little to support South Sudanese President Salva Kiir as Bashir’s assault on the Nuba people has resulted in an exodus of refugees into South Sudan. The humanitarian catastrophe is overwhelming by any measure but especially for a fledgling nation.

Last February I traveled to the Yida refugee camp and heard stories of indiscriminate bombing campaigns against civilian populations — a Khartoum trademark. I learned of murder, rape, starvation and pillaging. I spoke with people targeted for atrocities because of the color of their skin. Upon my return I issued a lengthy report with a series of policy recommendations — all of which I shared with senior administration officials; none of which were adopted.

Further, Kiir cannot count on the United States to be a reliable partner in pressing Khartoum to negotiate outstanding and deeply divisive issues in the peace agreement, including border delineation. Washington has repeatedly pushed the South to compromise with Khartoum, even in the face of persistent intransigence, violence and disregard for previous agreements from Sudan’s ruling National Congress Party.

Is Kiir South Sudan’s George Washington — a military man turned statesman? No. His tenure has been marred by a government that is rife with corruption and has little room for dissent. It was never going to be easy for decades-long rebel leaders to take on the mantle of governance.

Kiir’s rival and former vice president, Riek Machar, is a man with unbridled ambition dating back to the war between the North and the South, when as a rebel commander he was among those who mounted an unsuccessful coup against the much-venerated John Garang — considered the father of South Sudan — and later joined in an unholy alliance with Khartoum.

And underlying the internal politics are deep ethnic tensions that for years have been stoked by Khartoum in an effort to divide and rule.

It’s hard to venture a guess about how things might have turned out differently had Kiir and his government been able to focus on the immense domestic challenges, unburdened by threats from a hostile regime to the north.

But little is gained by rehashing past policy shortcomings, unless it is to learn lessons moving forward. And here I believe the lesson is that, as a guarantor of the peace deal between the North and the South, and having helped, in the words of John Kerry, “midwife the birth of this new nation,” the United States was and remains uniquely positioned to secure the success and flourishing of South Sudan. Will we embrace this responsibility before it’s too late?

I recently urged the Obama administration to recognize the wisdom of inviting former president George W. Bush and key members of his team, including former Sudan special envoy John Danforth, to engage in high-level diplomacy with the various actors involved. Unconventional? Perhaps. But it could be the key to saving South Sudan .

The Bush administration made Sudan a top foreign policy priority, and Danforth forged lasting relationships with Sudanese leaders as he helped negotiate the 2005 peace accord between the North and the South. They are well positioned to make the types of requests best made by friends.

Among the first messages Bush could take to Kiir is the need for him to release all political detainees. Such a move by Kiir would be viewed as a conciliatory gesture and the mark of a man willing to govern, even if it means making politically difficult decisions.

There also is a need to secure an immediate cease-fire, lest the world’s newest nation be thrust headlong into civil war, thereby joining the notorious ranks of failed states — and morphing in a matter of weeks from an American foreign policy triumph to an epic missed opportunity.

Clearly, there is a vital role for the international community in the days to come. But there is also a unique and exceptional role for principled American leadership. Obama must meet this crisis with the urgency, the ingenuity and the moral clarity it demands.

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