South Sudan government forces and allied militias have denied access to aid workers and looted relief supplies.
But peace is as distant as ever with an international community that appears paralysed, while the men ruling over the country's misery are unmoved by pleas for them to lay down their weapons.
There is no catastrophic drought in South Sudan, no natural driver for the famine afflicting 100,000 and threatening a million others.
Rather there is a nasty, stop-start three-year civil war in which starvation has become a battlefield tactic.
"Only a political plan to end South Sudan's national crisis, not food aid, can bring actual famine relief to South Sudanese," said Alan Boswell, a conflict analyst and writer on South Sudan.
The crisis is "not accidental but by design" Boswell said, adding that the government uses "food blockades as a weapon of war".
It is no coincidence that areas afflicted by famine are opposition areas, home to mostly ethnic Nuer and controlled for the most part by rebels, as a leaked report by United Nations investigators said.
"The bulk of evidence suggests that the famine in Unity State has resulted from protracted conflict and, in particular, the cumulative toll of repeated military operations undertaken by the government in southern Unity beginning in 2014," said the confidential 48-page report.
South Sudan government forces and allied militias have denied access to –- and sometimes attacked –- aid workers and looted relief supplies.
Michele Sison, the US deputy representative to the United Nations, told a Security Council meeting on Thursday that the government's obstacles to humanitarian work in the famine-struck areas "may amount to deliberate starvation tactics."
The United States, Britain and France on Thursday once again raised the idea of sanctions or a weapons embargo which was rejected by the Security Council in December with eight of the 15 members abstaining.
South Sudan's leaders fought for decades for independence, but once they got it in 2011, the fighting turned inward.
A long-standing power struggle between President Salva Kiir and his former deputy Riek Machar sparked fighting in Juba in December 2013 which quickly turned into a conflict throughout the country between Kiir's Dinka supporters and Machar's Nuer community.
It has been characterised by appalling brutality on both sides with ethnic massacres, the use of child soldiers, mass rape, sexual slavery, murder, torture, abduction and, in a few recorded cases, forced cannibalism.
Roughly a third of the population -– 2.5 million people -– have been forced from their homes while 5.5 million rely on food aid to survive.
East Africa's regional Intergovernmental Authority on Development (IGAD) was tasked with leading peace efforts, however these collapsed along with a 2015 power-sharing peace deal when conflict again erupted in Juba in July last year.
Since then the fighting has metastasised, spreading across the country and among ethnic groups jockeying for political and military advantage and to protect their communities.
Regional peace efforts have borne no fruit and the UN has been unable to push through an arms embargo or compel Kiir's government to accept the deployment of a regional protection force.
UN chief Antonio Guterres on Thursday denounced "a refusal by the leadership to even acknowledge the crisis or to fulfill its responsibilities to end it."
Instead, just days after famine was declared on February 20, triggering a ramping up of humanitarian efforts, Juba raised foreign worker visa fees a hundred-fold to as much as $10,000 (9,300 euros).
Foreign media access to South Sudan has also been curtailed with new bureaucratic barriers erected to deny access to journalists who have reported critically on the government in the past.
Critics say the silence of South Sudan's government and rebel leaders is fuelled by corruption.
"The ultimate prize is control of a kleptocratic, winner-take-all state with institutions that have been hijacked by government officials and their commercial collaborators for the purposes of self-enrichment and brutal repression of dissent," said John Prendergast, founder of the Enough Project advocacy group, who has many years' experience of South Sudan and knows its leaders personally.
Meanwhile, reports, including from the Enough Project, have exposed the squirreling away of money and the purchase of properties and luxury goods by leaders and their associates on both sides of the conflict.
"War has been hell for South Sudan's people, but it has been very lucrative for the country's leaders," said Prendergast.