On an official Mitt Romney campaign conference call this week, former New Hampshire governor John Sununu tested the latest effort to paint the commander in chief as disloyal to his country.

“I wish this president would learn how to be an American,” the Romney surrogate said.

Sununu, challenged, later apologized for the words — but not the sentiment. And that’s not good enough.

It’s not good enough because Sununu, like other prominent Republicans, is winking at those conservatives who continue to make the claim, often race-based, that President Obama is something un-American, something “other” than the rest of us. On Thursday, two days after Sununu’s attack, Romney himself said that Obama lacks “an understanding of what it is that makes America such a unique nation.”

Sununu and Romney are legitimizing people such as Cliff Kincaid. Also on Thursday, Kincaid convened his annual conference at the National Press Club for conspiracy-minded conservatives, this one about Obama and “Radical Islam.

On the program, Obama’s photo was alongside Vladimir Lenin’s and those of radical Muslim clerics. Kincaid got right to the point: Obama was actually sired by the late author Frank Marshall Davis, identified by Kincaid as a communist pornographer.

There is, Kincaid said, a “distinct possibility that Davis was Obama’s real father.” The host further informed the assembly that Davis was “Obama’s sex teacher” and that “Obama was under the tutelage of a pedophile.” Kincaid asked “what Frank Marshall Davis may have done to a young Barack Obama” and “what other terrible secrets are out there.” For more on this, Kincaid brought in a filmmaker to discuss his work on Obama and Davis, “Dreams from My Real Father.”

The next speaker, blogger Trevor Loudon, provided the additional information that Davis was a “possible Soviet spy” and that there are “a whole host of other communists and Marxists around Obama,” including Defense Secretary Leon Panetta, with “a communist-front record as long as your arm.” Loudon figures that Obama is making it possible for Russia and China to attack the United States and that “Latin American states would be invited in for looting rights.”

“You’ve got to ask,” Loudon said, “how involved were the Soviets in promoting the career of Barack Obama, and are they getting a payoff today?” (The Soviet Union dissolved in 1991, the year Obama graduated from law school.)

This isn’t to dignify the nuttiness. But it’s worth noting this latest symptom of Obama Derangement Syndrome, because some of these same people birthed the birther movement nearly five years ago and because this is the sort of craziness that Romney and prominent Republicans are furthering.

Romney has often shared the stage with Donald Trump, the most visible birther. And Romney’s surrogate Sununu followed his original allegation with the charge that Obama “has no idea how the American system functions” in part because he spent “years in Indonesia.”

At lower levels, Republicans are even more brazen. Rep. Allen West (Fla.) alleges that, in the House, “there’s about 78 to 81 members of the Democrat Party who are members of the Communist Party.” Rep. Michele Bachmann (Minn.) and four other House Republicans accused Huma Abedin, a top aide to Hillary Clinton, of being part of a Muslim Brotherhood conspiracy. Not to be outdone, Joe Arpaio, the sheriff of Maricopa County, Ariz., just came out with the fresh allegation that Obama’s long-form birth certificate is a forgery.

Such disloyalty allegations aren’t likely to stick to the man who vanquished Osama bin Laden and escalated drone strikes on terrorists. More likely, the charges will discredit the complaints from Romney that Obama is being unfair to him with his far tamer line of attack on Romney’s finances. Of greater concern, the disloyalty allegations from Republican officials will legitimize the sort of people who converged on the press club.

“Ladies and gentlemen,” Kincaid declared, “what we have today in the White House is somebody who could not survive any reasonable background check but is president, with access to America’s secrets.”

Loudon alleged that Alice Palmer, an early Chicago mentor of Obama, was a “high-level Soviet operative.” He added that if Obama loses in November, “he would just lay waste to everything he can. . . . You could see some serious violence in the streets of America.”

There was little time to fret about this, because the next speaker, Larry Grathwohl, began his presentation, on “reds exploiting blacks,” about how Obama is a “revolutionary mole” and part of a communist-Muslim plot with ties to Lee Harvey Oswald, Sirhan Sirhan and the Weather Underground.

Surely Sununu and Romney don’t believe this. So why do they encourage it?