You'd think with Carson being so nervous offworld (isn't he? Am I fanon-izing him?) that he'd think twice before going off without a guard, and isn't that protocol or something? He was very very stupid.

Still, I understand Rodney and Carson's instinctive reluctance to killing all those 'people'. Yes, I think there reluctance is very telling, but Carson just went past that and into dumb-ville.