Ellis believes that Mandela, whose worldview was fundamentally shaped by the national liberation struggles and Cold War tensions of the 1950s, was essentially out of touch with the world in which he found himself on leaving prison in 1990.
In a speech after his release, Mandela reiterated the African National Congress' commitment to the nationalization of banks, mines and industries at a time when free market economics was sweeping all before it.
"It was greeted with total horror, because nobody, even on the left, by 1990 was advocating state ownership of industry. That was all associated with a brand of socialism that had failed," said Ellis.
"He clearly knew almost nothing about the contemporary world. Before he had gone to prison, he was very pro-Soviet. When he comes out of prison the world had changed, and he had difficulty recognizing it."
As a consequence, Ellis said, the ANC leadership steered Mandela away from government and party affairs even when he was the South African president.
Instead, they preferred to use his moral standing and considerable charm as a focus for unity within both the highly factional ANC itself and wider South African society, and for fundraising and publicity purposes by having him pose for photos with the likes of Naomi Campbell and the Spice Girls.
But even after leaving office in 1999, Mandela remained fiercely outspoken in condemning what he saw as flagrant Western imperialism.
In 2003 he lambasted the United States and the United Kingdom for "attempting to police the world" over their military intervention in Kosovo in 1999 and the invasion of Iraq. He even suggested that moves to undermine the United Nations were motivated in part by the rise of a black African, Kofi Annan, to the office of secretary-general.
He also urged U.S. citizens to take to the streets in protest at moves to attack Iraq, accusing President George W. Bush of wanting to "plunge the world into a holocaust."
"If there is a country that has committed unspeakable atrocities in the world, it is the United States of America," he added.
Hain, then a minister in Tony Blair's British government, recalls Mandela phoning him at the time of the buildup to the invasion of Iraq, as enraged as he had ever heard him.
"He was just very angry and worried," Hain said.
"But I fully understood why; he is a man of principle. He would do things that offended the Bill Clintons and the Tony Blairs, like he would say to Fidel Castro, 'Thank you for supporting us,' and visit Cuba, or he'd do the same to Gaddafi in Libya."
Smith believes Mandela would have been deeply uncomfortable with efforts to deradicalize his legacy by portraying him in bland terms as simply an inspirational and reconciliatory figure.
"There are many people around him who believe he has been devalued by the use of his celebrity," he said.
"He stood for very firm anti-racist, anti-imperialist, anti-colonialist values. Yes, he would go and do business with the West, but ideologically he would always be first with Castro and independence leaders in Africa. First and foremost he was a black African, and that was where his heart and his politics lay."