Six months after an attack on a United Nations camp left dozens dead in South Sudan, an internal U.N. investigation concluded that peacekeepers made major errors that contributed to, and exacerbated, the massacre.

On Feb. 17, fighting broke out within the U.N. Protection of Civilians Site in the city of Malakal, first between young men from rival ethnic groups who had managed to smuggle guns through holes in the fence. Then the violence escalated after heavily armed government forces entered the camp.

A summary of the United Nation’s “board of inquiry report,” released Friday, said the organization and its peacekeepers failed through a “combination of inaction, abandonment of post and refusal to engage.”

In other words, some peacekeepers, whose most prominent mandate is to protect civilians, simply ran away once they were tested, abandoning sentry posts. Other peacekeepers demanded written permission to use their weapons, even though their U.N. mandate clearly gives them that authority.

But the failure began before the attack itself, according to the report. Peacekeepers did not heed warnings that violence was brewing, it said. The perimeter fence was poorly patrolled and left with gaping holes that could be used by combatants.

“Weapons and ammunition can easily be smuggled in and hidden,” the report said.

The end result was tragic, “ensuring that civilians would be placed in serious risk in the very location to which they had come for protection.”

It was not the first time the United Nations had failed to protect civilians, or the first time it had pointedly addressed those failings in a board of inquiry report (a list of others is below). Those investigations are meant to outline the ways the United Nations can improve its performance. But to many, they serve as reminders of how little the organization has learned from its own failures.

South Sudan, though, by the United Nations’ own admission, presents a wholly new challenge. More than 160,000 civilians are living in displacement camps where those inside are often targets of armed fighters outside. And sometimes it is unclear whether all the people inside, ostensibly in search of protection, are truly non-combatants.

Even if the peacekeepers had not fled, even if warnings had been heeded, could a violent clash in Malakal have been prevented? On that point, given the scale of the challenge and the limited resources of the U.N. Mission in the Republic of South Sudan, the report offers perhaps its most haunting assessment, arguing that civilians at the site “had unrealistic expectations for the protection that UNMISS could feasibly afford.”

Since its inception in 1948, the U.N. peacekeeping program has seen its share of successes. Missions in Lebanon and Sierra Leone are often cited as effective, as are many of the peacekeepers' deployments before the end of the Cold War. The agency was awarded the Nobel Peace Prize in 1988 for its work. But failures, such as those in Malakal, have roiled the program in recent years. Here are three other instances in which inquiries found that the United Nations and its peacekeepers fell short of their mandate to protect civilians.

1994: Rwanda

The Rwandan genocide, in which more than 800,000 people were killed, began after the Rwandan president’s plane was shot down as he returned from U.N.-brokered power-sharing talks between his Hutu-led government and Tutsi rebels. In the ensuing chaos, hard-line Hutus began to massacre more-moderate Hutus and Tutsis.

In a 1999 report commissioned by the United Nations, members of the independent inquiry issued a scathing condemnation of the response of the U.N. Assistance Mission for Rwanda:

“The Inquiry has found that the fundamental capacity problems of UNAMIR led to the terrible and humiliating situation of a UN peacekeeping force almost paralysed in the face of a wave of some of the worst brutality humankind has seen in this century.”

1995: Srebrenica

More than 8,000 Bosnian Muslim men and boys were killed in July 1995 by Bosnian Serb forces in a U.N.-designated safe area in Srebrenica, in the aftermath of the breakup of Yugoslavia.

The massacre was widely seen as a failure of the United Nations and its peacekeeping force. In his report on Srebrenica, then-U.N. Secretary General Kofi Annan acknowledged the agency’s failure:

“The fall of Srebrenica is also shocking because the enclave’s inhabitants believed that the authority of the United Nations Security Council, the presence of UNPROFOR [United Nations Protection Force] peacekeepers and the might of NATO air power, would ensure their safety. Instead, the Bosnian Serb forces ignored the Security Council, pushed aside the UNPROFOR troops, and assessed correctly that air power would not be used to stop them.”

2015: Central African Republic

Speaking Sept. 17, United Nations Secretary General Ban Ki-moon condemned sexual abuse allegedly carried out by U.N. peacekeepers. (UN Web TV)

Allegations of rampant sexual assault and exploitation by peacekeepers have plagued the mission in the past several years, prompting Ban in 2015 to call the problem “a cancer in our system.” Hundreds of women and children have come forward in the Central African Republic to report sexual assault by peacekeepers stationed there to stabilize the country after clashes between the government and rebels. The United Nations itself reported this year that girls as young as 13 were paid as little as 50 cents for sex by peacekeepers.

A 2015 report by an independent panel criticized the agency’s response to initial allegations of sex crimes:

“If the Secretary-General’s zero tolerance policy is to become a reality, the UN as a whole — including troop contributing countries — must recognize that sexual abuse perpetrated by peacekeepers is not a mere disciplinary matter, but a violation of the victims’ fundamental human rights, and in many cases a violation of international humanitarian and criminal law.”

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