This is what is likely to come of the arrest of Henry Louis Gates Jr. at his home by a white police officer: nothing.

The July 16 arrest of the African American scholar by a Cambridge, Mass., police officer looks a little more complicated and a lot more nuanced today than it did when the story broke last week. But it has sparked another conversation on ethnicity in America that, I suspect, will end as quickly as it began, with no clearer understanding of the roots of the reactions that fueled it. I’ll explain why in a minute.

We’ve made enormous strides in the 46 years since the Rev. Martin Luther King Jr. expounded on a dream of equality. America in 1963 envisioned neither a prominent, wealthy, and powerful black professor at Harvard nor a black president of the United States.

“I am standing here as testimony to the progress that’s been made,” President Obama said at the end of his news conference July 15 when asked about the confrontation in Cambridge. But then he added, “And yet the fact of the matter is, is that, you know, [ethnicity] still haunts us.” It certainly haunted Obama.

Two days after the president said he thought the police “acted stupidly” in the Gates affair, he stood in the White House briefing room to ask everyone — himself included — to “take a step back” from the heated rhetoric from all sides. He acknowledged that he “could have calibrated those words differently” and that the controversy shows that “these are issues that still very sensitive here in America.”

Obama’s comments were all the more noteworthy because he rarely speaks directly about ethnicity. Throughout the presidential campaign, he played it down. Only when the impertinent rantings of the Rev. Jeremiah Wright threatened to send his Oval Office ambitions the way of the Hindenburg did Obama speak up. He did so with a forthrightness that earned him plaudits for talking to the American people like adults about one of the country’s enduring ailments. It was a teachable moment — but, like most lessons, it was largely forgotten.

We’ve been down this road many times: an ethnic flare-up; talk for a week or so; then a rush to move on. Aside from the revelation of incendiary sermons by Wright (2008), there were the stiff sentences meted out to the Jena 6 in Louisiana (2007); the drowning of New Orleans after Hurricane Katrina (2005); the death of unarmed African immigrant Amadou Diallo in a hail of 41 police bullets in New York (1999); the dragging death of James Byrd in Jasper, Texas (1998); the New York police assault of Abner Louima with a plunger handle (1997); the Million Man March (1995); the arrest, trial, and acquittal of O.J. Simpson on charges that he murdered his white ex-wife and her friend (1994-95); and the beating of Rodney King by Los Angeles police officers (1991). All of these events sparked national soul-searching. And then nothing.

I was reminded of this enduring quest for understanding while doing research for this column. In 1999, when I was at the New York Daily News, I wrote an editorial lauding the one-year anniversary of what would be another failed attempt at dialogue: President Clinton’s national conversation on ethnicity. “Americans need to talk frankly and openly about the causes and effects of racism that people deal with daily,” I pleaded. “The fear and the misunderstandings. The anger and the resentment. For they have combined to make racism a corrosive cancer of the soul.”

This remains true today. The cure for this corrosive cancer won’t come through a government program or the courts. It won’t come through documentaries such as the ones that Gates says he wants to do on the criminal justice system or terrific movies such as Crash, the 2006 Oscar winner for best picture. This is a matter of the heart, an intensely personal exercise that demands we talk to each other — one on one, face to face. Perhaps over a beer, as Obama, Sgt. James Crowley, and Gates plan to do at the White House. But this requires trust.