JOHANNESBURG (Reuters) - Talks to forge South Africa's post-election unity government will need to bring together parties with goals as contradictory as seizing white-owned farms and mines, ditching Black empowerment policies and tearing up the constitution.
How well the African National Congress (ANC) harmonises these divergent and mutually hostile visions will determine the government's stability, its ability to make decisions and its policy priorities over the next five years.
It will also test Nelson Mandela's 1994 aspiration for a "rainbow nation at peace with itself", as politicians try to navigate historical ethnic and racial enmities that were starkly exposed by the May 29 election.
"It's polarised politics on steroids," Piers Pigou, Southern Africa Programme Head at the Institute for Security Studies, said. "It suggests we're going into a really messy, fluid period."
The ANC - which ruled unopposed for 30 years before losing its majority for the first time with just 40% of last month's vote - is racing to agree with its rivals on a unity government to keep it in power.
It has until parliament's first sitting on Friday to do so, and with several options on how to structure it. President Cyril Ramaphosa last week said his party would prefer a government of national unity involving a large number of parties - rather than a formal coalition with one or two.
Yet in the two weeks since the poll, far from seeking common ground, parties have hardened positions and exchanged insults.
Last week ANC chair Gwede Mantashe attributed the success of ex-leader Jacob Zuma's uMkhonto we Sizwe (MK) party - which came third - to "Zulu tribalism", prompting a backlash from Zulus and the MK who called his remark "dangerous and offensive."
Zuma has meanwhile claimed widespread fraud in an election observers and all the other parties deemed free and fair.
'OUTRIGHT REVOLT'
Mandela was the last leader to set up a national unity government, in 1994. Unlike Ramaphosa, the former liberation hero didn't do this out of political necessity but to reassure a nation divided by apartheid that no group would ever again be marginalised.
Last month's election revealed a South Africa no less divided along ethnic and racial lines than three decades ago.
"Parties that did well in this election ... campaigned on very narrow nationalistic identity politics," said Oscar van Heerden, an ANC insider, author and a senior research fellow at the University of Johannesburg.
The poll set back progress towards "a united, non-racial society", he said.
Speaking to Reuters, MK spokesman Nhlamulo Ndlhela rejected that view, and chided Mantashe for a "divisive" remark.
Still, the MK swept up nearly half of the vote in Zuma's Zulu heartland of Kwazulu-Natal, while the Democratic Alliance is still overwhelmingly popular with whites, and remains the biggest opposition party with 22% of the vote.
The far left Economic Freedom Fighters (EFF) command their biggest support among urban Blacks, while the ANC has strong loyalty among rural Black voters. The Patriotic Alliance, with 2%, campaigned to defend coloured people, as mixed-race South Africans are called.
Investors see a simple alliance between the ANC and pro-business DA as the most market-friendly. Yet ANC officials told Reuters such an option had been rejected by ANC heavyweights, some of whom - such as executive committee member Mathews Phosa - see the DA as the party of white privilege and a long-term vote loser.
The ANC is instead trying to dilute the influence of the DA in any coalition by having smaller parties join in.
"If Ramaphosa just went into a coalition with the DA ... that would be suicide for the party's unity," said Nicole Beardsworth, University of Witwatersrand research fellow.
She said the ANC had always been a broad church, comprising neoliberals like Ramaphosa and a left wing, including the Communist Party and Congress of South African Trade Unions, both of whom have raised concerns about a deal with the DA.
"So they need to bring in ... smaller, more radical parties in order to balance the demands from the left of the ANC."
But finding consensus that ends paralysis and creates a working government to kickstart South Africa's flagging economy is fraught with challenges.
"That's really where the rubber hits the road," said independent analyst Daniel Silke. "It makes ... cohesive policy-making extremely difficult."
The ANC and EFF for example, are committed to expropriating white-owned land for use by poor Black farmers, a policy the DA opposes. The DA wants to scrap Black empowerment policies that have mostly enriched a politically connected Black elite, a red line for the ANC.
Meanwhile the EFF and Zuma's MK party both want to overhaul the constitution, the former to put all land, water and mines to into state hands. The MK wants to replace it with one that would give more power to traditional chiefs.
Adding to the conundrum, the DA has ruled out working with either MK or EFF and Zuma's party says Ramaphosa must step down, a condition he has firmly rejected.
(Reporting by Tim Cocks; Additional reporting by Nellie Peyton in Johannesburg and Johnnie Isaac in East London; Editing by Silvia Aloisi and Ros Russell)