• World's newest country is a three-part series examining the challenges facing South Sudan.

Part 1: Can South Sudan limit internal strife?

Part 2: South Sudan's oil remains a sticking point

Part 3: Future of South Sudan tied to efficacy of foreign aid

When South Sudan becomes the world's newest country Saturday, its upcoming challenges will take a back seat to the euphoria surrounding the historic moment.

Still, internal conflicts loom large.

Before the young government can truly focus on the monumental task building a nation from scratch, it must first figure out a way to manage a range of pressing security issues.

Not only must the nascent, oil-rich country overcome the threat posed by its longtime enemy to the north – the Islamist-dominated government of Sudan's President Omar al-Bashir, who is wanted for war crimes by the International Criminal Court – it must also deal with militias, ethnic divides, and vocal critics within its own borders.

Analysts warn that if South Sudan's government does not seize the "independence moment" to begin a new chapter in the region's history, then it risks fulfilling the doomsday prophecies fueled by the northern government and other actors opposed to southern secession.

"Posturing along the border makes clear that [conflict] with the North is not over on July 9," says Zach Vertin, a Sudan analyst for the Brussels-based International Crisis Group, referring to ongoing North-South hostilities, such as running battles in the northern border state of South Kordofan and the tense stalemate over the contested Abyei region. "While there will undoubtedly be continued security attention in those areas, at the same time focus increasingly has to turn to the domestic situation both in political and security terms."

2,000 killed in six months

The United Nations estimates that nearly 2,000 people have been killed in the six months since southerners voted almost unanimously for independence in January.

Anti-government militia activity, severe army responses to the militias, and armed cattle raids that often spiral into local but deadly ethnic conflicts are the main causes of these deaths. The UN's latest statistics indicate that there are more than 260,000 people displaced in the South this year, which includes an estimated 100,000 who ran for their lives after the northern Sudanese army seized the disputed town of Abyei in mid-May.

The recent violence also illustrates that the grievances that southern tribes and armed groups have with each other – and with the southern government – are real and will not be resolved overnight.

Old wounds reopened

Conflicting priorities may well plague South Sudan's President Salva Kiir, who has been praised for bringing friends and foes alike into his government in the past five years. Mr. Kiir's strategy enabled the government to preserve the fragile southern peace that was ushered in when the north-south war ended in 2005.

When the war ended, healing the wounds between southern ethnic groups through political and military reconciliation was an essential task for the already bloated and at times dangerously dysfunctional army. But these wounds were reopened after Sudan's April 2010 elections, when the Sudan People's Liberation Movement (SPLM), the south's ruling party, used questionable tactics to secure its victory in some remote areas where opposition to its rule was strong.

Since the elections more than a year ago, these discontented groups have launched a flurry of rebel groups in the south's strategic oil-producing zones and clearly showing that the southern army is not fully equipped or capable of defeating these movements.

The southern army's attempts to defeat rebel militia groups have drawn criticism from not only from international rights groups, but also from southerners themselves, who say their grievances with the government should not make them enemies of their new state.

At a press conference on Wednesday in the southern capital of Juba, Minister of Internal Affairs Gier Chuang fielded questions from local journalists expressing concerns about the freedom of expression of journalists and of local officials who have recently criticized the government for failing to address rampant insecurity in remote areas of the south. Others complained of arbitrary treatment by security forces who are stepping up security measures in Juba ahead of Saturday's celebrations. Many Juba residents have been displaced from their homes and shops near the site of the ceremony.

'Kicks of a dying horse?'

But the southern government seems reluctant to acknowledge the security threats that plague its territory from within.

The minister of roads and transport told journalists in Juba on Wednesday that the rebellions causing insecurity and violence in four of the south's ten states are "just the kicks of a dying horse," and that they would not impact the ability of the government to implement the wide-ranging plans he described to build pipelines, railways, and ten international airports, among other huge infrastructure projects.

And Minister Chuang told reporters that many of the current security threats in the south have been caused by "different enemies of peace" seeking to destabilize the south and portray it "as a failed state even before it takes off."

Chuang echoed a familiar refrain of the southern government: that the northern Sudanese government is backing southern rebel movements. While this is certainly not impossible – and indeed was the case during the civil war – taking responsibility for addressing the real discontent of at least some of the southerners who have taken up arms against their government is a bitter pill that the southern government must swallow.

Seeking unity without a 'common enemy'

Aside from endangering the South's nascent economy and preventing foreign investment from taking off, internal insecurity may limit the southern government's ability to forge a unified nation out of its many diverse peoples.

“The new southern state will be born into a precarious position. It will be a weak state, but not a failed one," Jon Temin of the United States Institute of Peace told the Monitor. "The threats faced by the southern government will be a distraction, but they may also allow it to continue the narrative of the common enemy in the north that unites much of the south."

Mr. Temin argues that the greatest challenge facing the new state will be to move beyond the central forces that have kept southerners together until now: their "common enemy" and their collective goal of independence.

Working to define a southern national identity is a challenge to the SPLM, particularly because it still tends to address problems with a military mindset.

"The line between the military and the party is extraordinarily thin," says Vertin.

Creating an equitable and prosperous southern society is a decades-long task for the SPLM-led government, which watchdog groups including Human Rights Watch and the Carter Center have recently criticized for failing to open up political space to enable opposition parties to develop.

If conflict continues to shape the moves of Juba's ruling party, the SPLM may not manage to emerge with its democratic credentials intact.

The stakes are high for the young government, soon to be at the helm of one of Africa's most oil-rich countries. Failure will not only be a disaster for the southern economy, but also for the millions of southerners who fought hard with the hope that independence will usher in a much brighter future for their children and for the generations to come.