1 As this book was going to press, President Barack Obama announced late on the night of May 1, 2011, that Osama bin Laden, the mastermind of the Al Qaeda attacks of 9/11, was killed by a team of U.S. Navy SEALs in Pakistan. Declaring, “Justice has been done,” President Obama also said, “The death of bin Laden marks the most significant achievement to date in our nation’s effort to defeat Al Qaeda.” The history of Al Qaeda, those attacks, and the American response are recounted in the final chapter of this revised edition.