But recent KCNA articles use such racially-charged rhetoric that they have drawn criticism from the White House's National Security Council, which called them "particularly ugly and disrespectful."

A North Korean state-run news agency earlier this month launched an ugly, racist diatribe against President Obama, calling the U.S.'s first black head of state a "crossbreed with unclear blood." The agency also said that Obama "still has the figure of monkey while the human race has evolved through millions of years," and that "it would be perfect for Obama to live with a group of monkeys in the world’s largest African natural zoo and lick the bread crumbs thrown by spectators."

The most offensive piece, published in Korean on May 2 under the title "Divine punishment to the world's one and only delinquent Obama," repeatedly refers to him as a monkey.

"You can also tell this by his appearance and behavior, and while it may be because he is a crossbreed, one cannot help thinking the more one sees him that he has escaped from a monkey's body," it stated.

It's not unusual for North Korea's propagandists to hurl vitriol at state leaders — especially those from the U.S. and South Korea.

But the intensity and sheer volume of racial slurs in this latest piece surprised North Korea watchers.

Recently, KCNA has directed misogynistic slurs at South Korea's President Park Geun-hye, calling her an "indecent philistine and vile prostitute serving the U.S." They've accused her of bungling the Sewol ferry accident and criticized her close association with U.S., saying she has a mental disease.

The issue of race has special resonance in North Korea, where the Stalinist regime has gone to great lengths to instill a sense of racial purity in its citizens.

When North Korea talks about race, it's almost always important and telling about the state ideology.

Some academics — most notably B.R. Myers — argue that North Koreans fundamentally have a “race-based” worldview, showing more similarity to fascist Japan during World War II than Joseph Stalin’s Soviet Union. Myers condenses North Korea’s state orthodoxy into a sentence: “The Korean people are too pure blooded, and therefore too virtuous, to survive in this evil world without a great parental leader.”

That notion, of course, has been contorted to allow the most non-parental kind of leadership, but North Korea still goes to alarming lengths to maintain its racial purity. North Korean women often cross into China looking for work or an escape; if those women are impregnated and later forcibly repatriated to the North, they are subject to either forced abortions or infanticide.

The United Nations said in a recent human rights report that this practice points “to an underlying belief in a ‘pure Korean race’ in the DPRK to which mixed race children (of ethnic Koreans) are considered a contamination of its ‘pureness.’ ” The report referred to North Korea by its official name, the Democratic People’s Republic of Korea.

North Korea has proved its willingness to advertise all forms of contempt, racial or otherwise. Last month, its state news agency lashed out against the openly gay leading author of the U.N. human rights report, calling him a “disgusting old lecher.” And last week, the North called South Korean President Park Geun-hye an “old prostitute.”

There are some clear contradictions in North Korea’s stereotyping. The North maintains active ties with several African countries and just signed a cooperation agreement with Nigeria. Meanwhile, North Korea this year welcomed a team of former NBA players — most of them African American — for an exhibition basketball game attended by leader Kim Jong Un.