Al-Qaeda in the Arabian Peninsula (AQAP) has appeared as the group apparently behind the failed attempt to blow up an airliner travelling from Europe to the United States on 25th December 2009. The explosives involved (PETN and TATP) were like those used by the 'shoe bomber'. This article is mainly about the failed attack, with some comments on AQAP and the possible role of counterterrorism operations in Yemen.