By cunning chance, within a few days the President of United States has been asked to come to terms with his being of African descent, and to hike over that steep path which makes him everybody’s president. He was impressive when he exhorted black Americans to free themselves from paranoia. He told them not to keep blaming the society for their poor condition – and not to easily lump themselves all into one case. He presented himself as the living example of an achievement that, in principle, is possible for everyone. But then came the case of Henry Louis Gates Jr., a prominent African American Harvard scholar, who was arrested at his home by a cop looking for a burglar.

It looked like a solemn denial of Obama’s egalitarian optimism, easily frustrating for people of the ghetto. That’s why he accused the police of behaving "stupidly" with Gates, a friend of his; he warned against racism, which is not yet defeated in America. But he also had to take back those words after the protests of conservatives and complaints of police.

Officer Crowley - accused of misuse of power - says that it’s legal to suspect someone who, not being able to use his keys, breaks into his home. And that the law allows the use of handcuffs when in a confrontation with someone using epithets towards a cop. "You don’t know who I am": that’s perhaps what the arrogant Gates said to Crowley, who may be unskilled in academy titles and sophisticated talk-shows. If this is true, the incident would paradoxically suggest a kind of reverse racism, practiced against a middle class white citizen, less talented and cultured than a highly successful black man.

Be that as it may, Obama apologized to the cop and invited him and Gates to the White House for a conciliatory meeting. The president settled with the idea that they both crossed the line. But the incident has been a less than ideal chance to lay bare taboos and latent impulses of America’s veins; it showed how difficult it is, even for a brilliant Obama, to guard against old prejudices.