The Obama Administration lost one of its most outspoken members at the weekend when Van Jones, the President’s “green jobs czar”, resigned after it emerged that he had signed a petition claiming that senior US government officals deliberately allowed the terrorist attacks of September 11, 2001.

The departure of Mr Jones, an environmental and civil rights activist with a law degree from Yale, came as an unwelcome embarrassment for a President trying to rescue his domestic agenda while under increasing attack from Republicans.

Mr Jones’s appointment was not subject to congressional approval, but critics said that he was responsible for tens of billions of dollars in government spending on programmes designed to boost the sustainable energy sector while stimulating the economy.

In addition to signing up to the 9/11 conspiracy theory petition in 2004, he was caught on video calling Republicans “a**holes” at a public meeting last February, before his appointment.

Described by his publisher as the first African-American to write a bestseller on the economy and the environment (The Green Collar Economy, published last year), Mr Jones was a campaigner against racism — and, apparently, against capitalism — before adopting green issues.

He has said he was radicalised by the Rodney King case, in which white police officers in Los Angeles who severely beat Mr King were acquitted in a 1992 trial that triggered the worst riots in the city’s history.

“I was a rowdy nationalist on April 28, and then the verdicts came down on April 29,” he told a newspaper in 2005. “By August I was a Communist.”

For Republicans who publicised Mr Jones’s indiscretions, his past politics are less important than his closeness to Mr Obama, and his role as one of an expanding cadre of czars whose power conservatives want to curb.

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