1. Bin Laden did not use civilians as a shield to protect himself when he was being encircled. But Prabakharan who proclaimed as the savior and the only representative of the Tamil people used the very same people to protect himself putting them at great risk.
2. As per the news coming out, Bin Laden did fight back the American forces and was shot at his head. He refused to surrender while Prabkaran died cowardly fleeing the fighting and sending his body guards/suicide carders to fight the SL army. As per the account of the Copral Ranbanda who apparently shot dead Prabakaran the latter was shouting in filth at his suicide carders to explode themselves against SL army.
3. It was the ground forces of Sri Lankan army that killed Prbakharan unlike Americans who used mainly its Air Force to kill Bin Laden in fear of losing its ground forces. One of primary reasons for SL forces to use her ground forces was to protect the civilians while losing their own men in great numbers.