Exactly why the three Qatari men named in the Doha embassy document in February last year were not mentioned in the exhaustive 9/11 Commission report is unclear. But they did appear in an FBI list of more than 300 people investigators wanted to speak to in 2002, and the two-page embassy cable, typed in block capitals and sent in February 2010, leaves no doubt that US investigators believe they could have been part of the plot.