Is Osama bin Laden one of the biggest terrorist in the world?

He was, until he was killed by US forces in 'Operation Neptune's Spear'

Now, the most wanted man is 'El Chapo' Guzman, Mexican drug lord and head of the Sinaloa Cartel. He is #1 on the FBI's most wanted listed with a reward of $25M, plus Mexican authorities are also offering $5M.