Barack Obama in a 1978 senior yearbook photo at the Punahou School. (AP Photo/Punahoe Schools, File)

We are at risk of running out of dead horse to flog, but there's one more aspect of former New York City mayor Rudy Giuliani's anti-Obama comments that's worth isolating. Speaking with reporters from the New York Times, Giuliani denied that his statement that President Obama doesn't love America was related in any way to the president's race. "This isn’t racism," Giuliani said. "This is socialism or possibly anticolonialism."

Socialism doesn't require any further explanation (unless you're a Millennial); Giuliani is suggesting that Obama is an opponent of capitalism. But what's the "anticolonial" thing?

As with many anti-Obama sentiments, that particular charge can be traced back to Dinesh D'Souza. In September 2010, Forbes ran an excerpt from D'Souza's upcoming book "The Roots of Obama’s Rage." "To his son," it reads, referring to Obama's father, "the elder Obama represented a great and noble cause, the cause of anticolonialism. Obama Sr. grew up during Africa’s struggle to be free of European rule, and he was one of the early generation of Africans chosen to study in America and then to shape his country’s future."

D'Souza defines anticolonialism as "the doctrine that rich countries of the West got rich by invading, occupying and looting poor countries of Asia, Africa and South America" -- which is somewhat more specific than others might offer. Colonialism generally refers to the era in which European nations (and others, including the United States), occupied other countries as satellite states. Think: "The sun never sets on the British empire." Anti-colonialism, in the broadest sense, is opposition to that practice.

The argument over anti-colonialism predates D'Souza, of course. For a century, opposition to imperialism was intertwined with communist politics. In part, that was a function of the place of communists outside the political power structure. And in part, it was resonant with countries seeking to declare their independence. At the Second Congress of the Communist International in 1920, the group linked colonialism and capitalism. (Among the theses: "The loss of the colonies and the proletarian revolution in the mother countries will bring the downfall of the capitalist order in Europe.") Friedrich Engels theorized about an uprising in colonial India in 1882. Ho Chi Minh complained about French colonialism in Vietnam in 1923. In a speech in 1961, Che Guevara saw Cuba as the launching point for an anticolonial wave. "Victory by the popular forces in Latin America is clearly possible," he said, which could be "the first stage in completely destroying the superstructure of the colonial world."

Anticolonialism, in that sense, meant curtailing the power of Western/capitalist nations. So when Giuliani draws a distinction between socialism and anticolonialism, it's less distinctive than it might seem.

The argument D'Souza makes to prove his point, by the way, is heavily circumstantial. He runs a thread from Obama's father (with whom, remember, Obama did not grow up) to anticolonial thinkers of the era in which he lived. D'Souza quotes one line from a book written by an academic, noting that this person taught Obama at Columbia. "It may seem incredible to suggest that the anticolonial ideology of Barack Obama Sr. is espoused by his son," D'Souza writes, correctly. But: "That is what I am saying." Obama "adopted his father’s position that capitalism and free markets are code words for economic plunder" -- despite Obama's having essentially no contact with him.

With the 2012 election approaching, Newt Gingrich embraced D'Souza's argument. To the Post's Robert Costa (then at the National Review), Gingrich declared that D'Souza had made a "stunning insight." What if [Obama] is so outside our comprehension," he said, according to Costa, "that only if you understand Kenyan, anti-colonial behavior, can you begin to piece together [his actions]? That is the most accurate, predictive model for his behavior."

Gingrich's comments kicked up much more furor than D'Souza's, given that the former speaker of the House planned to run for president. A reporter dug up Gingrich's avowedly pro-colonial dissertation, while the Los Angeles Times lamented that "Gingrich used to be a serious figure." The topic faded.

Until this week. What prompted Giuliani to throw the expression into the mix isn't clear. It was, perhaps, simply a less contentious rationale than racism. Which is true. But that doesn't necessarily make his comments much more believable.