As the celebratory chants of "U-S-A! U-S-A!" die down, oneAmerican's reaction to Osama Bin Laden's death is causing an uproar. PittsburghSteelers running back Rashard Mendenhall tweeted, "What kind of personcelebrates death? It's amazing how peoplecan HATE a man they have never even heard speak. We've only heard one side. " And for good measure, he added a 9/11Truther-tingedtweet: "We'll never know what really happened. I just have a hard timebelieving a plane could take a skyscraper down demolition style." Steelerspresident Art Rooney says he can't explain or comprehend what Mendenhall meant,but that the team is "very proud" of what American troops accomplished. Thisisn't the first time Mendenhall has generated controversy on Twitter. In Marchhe expressed support for Minnesota Vikings running back Adrian Peterson when hecompared the NFL to modern-day slavery.