WHY IT MATTERS: Issues at stake in election - Article Photos 17/40

FILE - In this Nov. 10, 2009, file photo, a memorial to victims of the Fort Hood shooting is shown before the start of a memorial service, to be attended by President Barack Obama, at Fort Hood, Texas. Osama bin Laden is dead and there hasn’t been a successful attack by al-Qaida-inspired extremists on U.S. soil since the deadly shooting rampage in Fort Hood, Texas, in 2009. But the danger of terrorism remains a reality for Americans, as seen in the attack in Libya in September that killed U.S. Ambassador Chris Stevens and three other Americans. (AP Photo/Donna McWilliam, File)