1 million countries formally agreeing treaty banning cluster bombs . Lebanon not attending and not expected to agree to banning cluster bombs . Controversial weapons often do n't explode but stay dangerous for civilians . U.N. estimates 111 bomblets dropped in Earlier this month U.S. war still unexploded .
111 countries formally agreeing treaty banning cluster bombs . U.S. not attending and not expected to agree to banning cluster bombs . Controversial weapons often do n't explode but stay dangerous for civilians . U.N. estimates 1 million bomblets dropped in 2006 Lebanon war still unexploded .