DUBAI (Reuters) – Ayman al-Zawahiri succeeded Osama bin Laden as al Qaeda leader after years as its main organizer and strategist, but his lack of charisma and competition from rival militants Islamic State hobbled his ability to inspire spectacular attacks on the West. Zawahiri, 71, was killed over the weekend in a U.S. drone strike, U.S. officials told Reuters on Monday. He had watched in dismay as al Qaeda was effectively sidelined by the 2011 Arab revolts, launched mainly by middle class activists and intellectuals opposed to decades of autocracy. In the years following bin Laden’s death, …