Cyril Ramaphosa and Barack Obama in Johannesburg in JulySiphiwe Sibeko / Reuters

In July, an American ex-president stopped briefly in South Africa. Barack Obama had forgotten the season in the Southern Hemisphere, he told an audience, and had needed to send an aide to buy a coat for him. The opportunity to lecture reminded him of the gray-haired ex-professor he might have become had he not entered politics. He thanked his hosts, calling South Africa’s new president, Cyril Ramaphosa, “inspiring,” and spoke at some length about the legacy of an earlier president, Nelson Mandela.

Obama’s appearance, and the compliment to his host, set off the chain of events that culminated Wednesday in President Donald Trump’s decision to intervene, via tweet, in the fraught politics of postapartheid land reform in South Africa. The tweet itself is important in the way anything the current American president says is, but its content matters far less than its context. Trump’s interference in another country’s internal affairs shows that his idea of the American national interest has become a thinly veiled tool for pushing a narrow, partisan ideology that has little to do with the traditional process of making foreign policy. Instead, it has everything to do with the president’s media consumption.

The tweet was largely false. He said he would order the U.S. secretary of state to “study the South Africa land and farm seizures and expropriations and the large scale killing of farmers.” (South Africa is debating the rules for seizing land, not actually seizing it, and there is no large-scale killing of farmers.) Helpfully, Trump provided his source: the Fox News host Tucker Carlson, whose show had just covered the issue.

The Fox host is the link connecting Trump’s statement back to Obama. Earlier this summer, Carlson covered Obama’s speech, tying it to land-reform efforts in South Africa. Ramaphosa’s government is in the midst of a political battle over how aggressively to expunge the legacy of apartheid, which left the ownership of land heavily skewed by the country’s decades-long policy of official white supremacy. His ruling African National Congress (ANC) party has for decades had a policy of redistributing land, but to date has only pursued transactions between willing sellers and buyers. Facing a serious political challenge from the left in upcoming elections, the ANC under Ramaphosa has dropped that policy and is moving to amend the constitution to allow the government to take land without paying for it in certain cases, a policy that’s become known as “expropriation without compensation.” Carlson believes that policy is racist, since it would be used to take land owned by the families that benefited from apartheid, which are, unsurprisingly, white. “Obama knew all this, and he described this as ‘inspiring,’” Carlson said. (Obama did not reference land reform in the speech.)

Since that segment, the lie that Obama supports the theft of white South Africans’ land has become a white-supremacist talking point. YouTube hosts a version of the earlier segment with the description, “Obama In South Africa Praises White Genocide Leaders.” (There is no white genocide, but the idea of it is popular in white-supremacist circles, and the racist Charleston murderer Dylann Roof has aligned himself with the remnants of apartheid.) The hard-right cartoonist Ben Garrison drew a leering Obama standing over Ramaphosa’s shoulder as the South African state steals farmland from tearful whites. (This theft is not occurring, and not pictured are the millions of black families that struggle for access to land.) In the new Fox News segment that Trump referenced, Carlson picked up the talking point again, saying that Obama had praised a racist South African government. Carlson was careful not to explicitly make the false claim that Obama supports land seizures, but the effect is clear. According to Carlson, the U.S. State Department claimed that “President Ramaphosa has pledged that the process will follow the rule of law.” But, Carlson argues, “the State Department did not mention that by following the rule of law, he is changing the constitution to make it possible to steal land from people because they are the wrong skin color.”

Trump’s tweet makes it explicit that Carlson’s segment was the inspiration for his new foreign-policy move. It caught the State Department flat-footed. It’s hardly the first time under Trump that his officials don’t know the policy: When the president met with Russia’s Vladimir Putin in Helsinki, his secretary of state couldn’t convince senators that the president had briefed him on the conversation. The New Yorker’s Susan Glasser has called this “the breakdown of American foreign policy.” The vast apparatus built to support the American leader’s decision making is cut entirely out of the loop. Instead, the president makes calls purely based on what he sees on television.

Even beyond that problem, the inversion of American support for “rule of law” abroad is especially dangerous. Supporting the rule of law has been a core mission of U.S. diplomacy for decades. Trump is seizing that means of influence and using it to support a thinly veiled white-supremacist cause. The conception of law Carlson is pushing, and which Trump now says he backs, puts process above any other consideration. It doesn’t matter that some South African farmers came by their land because a racist minority seized it from the people who lived there; on this view, what’s important is that they own it now and must be compensated for its seizure. This kind of empty formalism is, coincidentally, exactly the way the rule of law is practiced in Russia. Crimea is Russian, Putin claims, because its residents voted to join Russia. No matter that the referendum was preceded by a Russian invasion.

The result of Trump’s approach is not just a diplomatic fight with South Africa, but the tainting of a swath of American foreign policy. Obama, speaking in South Africa, seemed to presage this. “We now see much of the world threatening to return to an older, a more dangerous, a more brutal way of doing business.” To counteract that, he continued, “we have to start by admitting that whatever laws may have existed on the books, whatever wonderful pronouncements existed in constitutions, whatever nice words were spoken during these last several decades at international conferences or in the halls of the United Nations, the previous structures of privilege and power and injustice and exploitation never completely went away.” That was true of apartheid South Africa. It is true in America today.

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