The Islamic State released a video on Sunday in which one of the assailants in the Paris terror attacks posthumously claims that he carried out the attack in the name of the group. The video shows Amedy Coulibaly, the man who killed four hostages at a Paris supermarket on Friday before he was fatally shot by police, pledging allegiance to Islamic State leader Abu Bakr al-Baghdadi. Speaking in French and occasionally lapsing into broken Arabic, he is shown wearing a flak vest, then a leather jacket and later a traditional African robe while he explains his motives for carrying out...