The Texas synagogue siege, which ended on Saturday with the killing of a British terrorist and the release of his four hostages, has been a much bigger story in the United States than in this country. Americans, especially if they are Jewish, are demanding to know how such an outrage could have happened. At least one associate of Malik Faisal Akram, the hostage-taker, is still being sought there. Yet the incident leaves a worrying legacy here, too: not only for the Greater Manchester police, still interrogating two teenagers in custody, but for the Muslim community in which Akram lived until recently.