It was reported that Osama bin Laden was unarmed when he was killed?

Why would the US govt NOT want to take him alive? How is it that Saddam Hussein was captured alive and unarmed but not Bin Laden? Wouldn't interrogating the man on top of the Al Qaeda pyramid have unraveled the entire network and opened up new info regarding 9/11? Why after 10 yrs,2 wars,5000+ american deaths,countless iraqi and afghani deaths,trillions of dollars, Loss of several freedoms and a the biggest worldwide manhunt in history for the man who was behind this was he not captured and interrogated? Kill him? Ok sure, but why not after finding out what he knows,and knew?