During a major policy speech on healthcare, even President Obama found time to weigh in: "… I think it's fair to say, number one, any of us would be pretty angry. Number two, that the Cambridge police acted stupidly in arresting somebody when there was already proof that they were in their own home. And number three – what I think we know separate and apart from this incident – is that there is a long history in this country of African-Americans and Latinos being stopped by law enforcement disproportionately…" Needless to say, the next morning's papers talked about Obama calling Cambridge police "stupid".

The arrest of Harvard professor Henry Louis Gates has been officially swallowed by the larger narrative of race in America. Now I love a good racial escapade as much as the next person, but this one strikes me as uniquely unfortunate both in its timing and its capacity for becoming a flashpoint for unrelated resentments.

The facts not in dispute are straightforward. Gates came home from a trip and found his front door jammed. With the help of his driver, he tried to push the door open, unsuccessfully. He then went to the back door, opened it with his key, turned off the alarm system and called Harvard's property management company to report the sticky door. Meanwhile, a passerby called the police to report that "two black males" were breaking into a house. When the police arrived, they encountered Gates in his living room. Gates provided his driving licence and his Harvard ID.

Here the stories diverge. Gates says he asked the officer to identify himself and the officer refused. The officer says that Gates was unco-operative, called him a racist and began shouting so loudly – "Your momma!" and: "You don't know who you're messing with!" according to the police report – that the noise constituted "tumultuous behaviour" and "public disorder". Gates was handcuffed and hauled off to jail for a few hours. A day later, a judge dismissed the charges, saying both sides had acted badly. Gates demanded that the arresting officer apologise; the officer demanded that Gates apologise. The Cambridge police department demanded that President Obama apologise, which he did, quite eloquently as usual. Gates took to national television to set the record straight. Al Sharpton announced his intention to march in protest. And Michael Jackson, pushed from the front pages for a hot minute, was finally able to rest in peace.

Most unfortunate, but as American crime blotters go, this one is no big deal. Yes, racial profiling is an endemic, massive problem, but in this instance the police were called because of at least minimally suspicious behaviour – two men trying to force open a door. And yes, (allegedly) shouting angry taunts at the police isn't tea-time politesse, but it does seem that the officer might have responded to it in a more professional manner than elevating it to the level of public "tumult".

What makes this case so interesting – and alarming – is the vitriolic public commentary that ensued. Early newspaper and on-line accounts helped seed confusion, varying wildly: some gave the impression that Gates was trying to break into a house not his own, some that he refused to identify himself or that he resisted arrest. None of that was true.

But the larger backlash has quickly moved from the individual incident itself to condemnations in the stereotyped plural, concentrating on a very tight set of recurring themes: Gates is "uppity", arrogant, pseudo-educated. He should have been grateful that the police came to his house at all. Harvard was stupid for hiring him. African-American studies, the department Gates chairs, is a non-subject, only on the curriculum to keep black students from rioting. The Ivy League is run by politically correct "wusses" who don't have the courage to get rid of "undeserving" "whiners". Who could blame police officers for refusing to come to black homes or neighbourhoods if this is what they get? "Those people" have jobs a "more qualified" white person should be holding.

(Where, oh where, our fleeting "post-racial" moment of Kumbaya?)

I mentioned that timing was also a probable factor in this brouhaha. The entire week before Gates's arrest was consumed with reports of the congressional hearings for Obama's Supreme Court nominee, Judge Sonia Sotomayor. She would be the first Hispanic and only the third woman sitting in our highest court. Hence, racial resentment had already been simmering on the shock-jock media burners. Three ultra-conservative senators in particular grilled her, day after day, using some of the most prejudiced, stereotype-laden language we've heard publicly in many a year. Despite the fact that Sotomayor graduated at the top of her class from Princeton and Yale Law School, she has been attacked as not qualified, chosen not for merit but because she's a woman or Latina. Pundits such as Pat Buchanan railed that "affirmative action is to increase diversity by discriminating against white males". Furthermore, said Buchanan, there could be nothing wrong with a court of all white men, because, after all "white men were 100% of the people who wrote the constitution, 100% of the people who signed the Declaration of Independence, 100% of the people who died at Gettysburg and Vicksburg…"

Then, too, controversy erupted over a statement Sotomayor made years ago, in which she hoped her life experience as a Latina woman would lend her wisdom in ways that might allow her easier insights into situations that others might not have lived through. This, the so-called "wise Latina woman" statement, has got her relentlessly labelled a "reverse racist" by the shock-jocky press.

Finally, Judge Sotomayor was part of a panel of judges that ruled, based on established precedent, that a hiring test given by the New Haven fire department should be scrutinised for bias, after all the African-American applicants and all but one Hispanic failed the test. Coincidentally, barely a month ago, the conservative majority of the Supreme Court narrowly overruled that holding, saying that disparate impact was not alone sufficient to strike down the test – and that it was "racism" against the white firefighters who did pass the test. As a visual flourish, during Sotomayor's hearing, row upon row of New Haven firefighters (in uniform, all white men but for that lonely Hispanic) sat in on the hearing, there to object to her nomination. The cameras loved it, panning their solemn faces relentlessly.

In short, the Sotomayor hearing and the New Haven firefighters case have reignited the general American debate about affirmative action. So when the extremely distinguished Harvard university professor Henry Louis Gates was carted off in handcuffs, allegedly calling out: "This is what happens to black men in America!", there was a distinct shimmer of schadenfreude in some parts of the national psyche. The reactionary themes that had been percolating during the last few weeks came bursting to the fore: minorities are taking over! Obama is only appointing non-whites! White people are the truly oppressed! People of colour, particularly ones who went to Harvard, Yale or Princeton, are reverse racists.

The arrest itself is hardly the best example of either racial profiling or police-state oppression. But the discourse that has welled up in its wake reveals a public inclination that is marred by that and more.

Patricia Williams is professor of law at Columbia University