11.39am: Jay Rosen, from the journalism institute of New York University, describes the White House response to the leak as "unimpressive", adding his own observations to the points made by the US government:

• This leak will harm national security. (As if those words still had some kind of magical power, after all the abuse they have been party to.)

• There's nothing new here. (Then how could the release harm national security?)

• Wikileaks is irresponsible; they didn't even try to contact us! (Hold on: you're hunting the guy down and you're outraged that he didn't contact you?)

• Wikileaks is against the war in Afghanistan; they're not an objective news source. (So does that mean the documents they published are fake?)

• "The period of time covered in these documents … is before the president announced his new strategy. Some of the disconcerting things reported are exactly why the president ordered a three month policy review and a change in strategy." (Okay, so now that we too know the basis for the President's decision, that's a bad thing?)

Our attitude throughout human history has been to experience events like these and then put safeguards in place," says Bostrom. "That strategy is completely futile with existential risks. By definition, you don't get to learn from experience. You only have one chance to get it right.