Shimon Peres was less hawkish than the likes of Netanyahu and Lieberman, but for President Obama to compare him with Nelson Mandela is simply ahistorical.

President Obama, speaking at the funeral of Shimon Peres, his fellow Nobel Peace Prize winner, said the former Israeli president and prime minister “reminded me of some other giants of the 20th century that I had the honor to meet … like Nelson Mandela.”

It’s unlikely the comparison would have pleased Mandela.

In 1974, while Peres was Israel’s minister of defense, he privately visited leaders of South Africa’s white-supremacist government in Pretoria. Afterward, according to documents unearthed by author Sasha Polakow-Suransky in The Unspoken Alliance: Israel’s Secret Relationship with Apartheid South Africa, Peres wrote a letter to his hosts thanking them for helping to establish a “vitally important” link between the two nations.

“This cooperation is based not only on common interests and on the determination to resist equally our enemies, but also on the unshakeable foundations of our common hatred of injustice and our refusal to submit to it,” Peres wrote.

In 1975, Peres met with P.W. Botha, then South Africa’s defense minister, in Switzerland and offered nuclear weapons technology to Botha’s government, The Guardian newspaper reported, quoting further documents from Polakow-Suransky.

Meanwhile, Mandela, also a future Nobel Peace laureate, was in prison, serving what turned out to be a 27-year sentence for conspiring to overthrow the apartheid government.

He and Peres may have eventually reconciled. Peres, who was critical of apartheid in his public statements, said after Mandela’s death in December 2013 that “the world lost a great leader who changed the course of history.” Photos abound of the two men smiling and shaking hands or embracing.

But Israel had been one of South Africa’s strongest and most consistent allies during the period of white rule. That alliance, and its implication for human rights, are not subjects that the Tel Aviv government or its friends in Washington discuss in public—a silence that became even more pronounced with Obama’s oration at Peres’ funeral.

The White House press office declined to comment on the subject.

World leaders, even Nobel Peace Prize winners, do not lend themselves to easy assessments of their character or their consistency. Mandela’s heroic and primarily nonviolent battle against apartheid also included years of guerrilla warfare. Obama’s advocacy of nuclear disarmament was a principal reason for his award in 2009, but after fruitful negotiations on nuclear issues with both Russia and Iran, he has begun a $1 trillion upgrade of the U.S. nuclear arsenal.

Peres was honored for his work on the 1993 Oslo Accords, a framework for peace between Israel and the Palestinians. In the jumbled world of Mideast relations, Obama’s portrayal of the late Israeli leader as a man of peace was supported by at least some evidence.

Yet one of the principal reasons for Oslo’s failure has been the steady expansion of Israeli settlements in occupied territory, in defiance of international law. And many years before Oslo, it was Peres, as defense minister, who championed the movement with the slogan “Settlements everywhere.”

When Hezbollah fired missiles into Israel in 1996, Peres, then acting prime minister, launched a 16-day bombardment of Lebanon known as Operation Grapes of Wrath. One-hundred-six civilians were killed when Israeli forces shelled a United Nations compound in the Lebanese village of Qana.

Peres, by most accounts, was less hawkish, more open to negotiations and possible reconciliation, than current leaders like Prime Minister Benjamin Netanyahu and Defense Minister Avigdor Lieberman. But he was no Mandela.

For Obama to say otherwise, with the eyes of the world on him, may have been good politics. But it was very bad history.