THE case of six black schoolboys who were charged with a string of offences, including attempted murder, after a white classmate was kicked unconscious in Louisiana, has blown open one of the most sensitive fault lines in American politics and revived charges that Barack Obama, the presidential candidate, is not “black enough” to win the support of African-Americans.

The dispute over the “Jena Six”, with its explosive reminder of America’s hidden racism, could help Hillary Clinton consolidate her vote among the black community at the expense of Obama, who is lagging nearly 20 points behind her in the race for the Democratic nomination.

America has been rocked by a series of high-profile cases with ugly echoes of the South’s history of segregation and lynchings. It recently emerged that Megan Williams, a 20-year-old black woman, was held captive, raped, stabbed and forced to eat faeces at a farm in West Virginia. Six members of a white family have been charged with kidnapping and torturing her.

Last week thousands of demonstrators marched through the small, largely white town of Jena in protest at the treatment of the six teenagers said to have attacked Justin Barker, a white boy, after being taunted by three nooses strung from a playground tree that was considered for “whites only”.

While a handful of white boys were briefly suspended from the school after a series of confrontations, the black students, aged between 14 and 18, were expelled and charged with serious offences, even though the victim recovered quickly enough to attend a school function that evening.

Some of the charges were later reduced but one boy, Mychal Bell, remains in jail. The tree has been cut down.

Obama did not attend last week’s march, provoking Jesse Jackson, a veteran of civil rights protests, to complain that the Illinois senator was “acting like he’s white” – though Jackson later said he could not remember using those words. He did say: “If I were a candidate, I’d be all over Jena” – a pointed reference to Obama’s seeming lack of commitment to what has become a touchstone civil rights issue.

B L Moran, a local pastor who is helping the black youths, complained: “Look at all these people who have come from all over the United States. We have not seen anyone of his stature.”

While Obama kept his distance, Clinton enjoyed an easy ride on Al Sharpton’s agit-prop radio show last week where she proclaimed: “We cannot let this kind of inequality and injustice happen anywhere in America.”

Sharpton, like Jackson, has previously stood for president and been heavily defeated, not least because he was identified as a radical single-issue campaigner for black rights. But the more Obama has sought to avoid this trap, the more pitfalls it has created for him.

An African-American adviser to Obama said it would be unwise for him to follow the model of Jackson and Sharpton. “It is unfair to expect him to be a national spokesman for black folk,” the adviser said, adding that Obama also had to deal with the “issue of jealousy” in that “he is considered an upstart who is not as black as we are”.

Debra Dickerson, an African-American writer, caused a furore this year when she pointed out what she called the obvious. “Obama isn’t black,” she wrote, in the sense of being descended from west African slaves. Whites were able to swoon over him but blacks regarded him as an outsider, she claimed.

Michelle Obama called last month for a halt to the charge that her husband, the son of a white mother with slave-owning ancestors and a black father from Kenya, was not black enough.

“We are messing with the heads of our children,” she said.

Dickerson said last week it was unfair to expect Obama to pander to Jackson and Sharpton. “I don’t think he had to be at Jena. He is not a civil rights person, he is an elected public representative. Barack Obama has to answer to everybody.”

However, she predicted that Clinton would win more black votes than Obama. “We’re all very proud of Obama and would like our daughters to marry him, but I really see black people voting for Hillary Clinton. I think it makes sense. We’ve no doubt she will fight hard for us. She has a relationship with black people going back 20 years.”

In South Carolina, a must-win primary state for Obama, a recent poll of black voters showed him only four points ahead of Clinton, whose standing is boosted by the popularity of her husband, the former president Bill Clinton.

Race is also proving to be an awkward issue for the Republican candidates for president. All the leading contenders turned down an invitation to participate in a nationally televised debate this week at a historically black university in Baltimore.

President George W Bush obliquely criticised their decision to stay away, saying: “My advice to whomever will be our nominee is to reach out to the African-American community.”

See a video of the march in support of the Jena Six

Times Recommends

• Obama: the world can expect better of America
• Gulp! Mystery killer threatens French oyster
• Secret of Northn Lights key to space safety