They will just usually say "let the others do it". Game theory says that all parties could be better off by co-operating but if you get benefit if you defect w

They will just usually say "let the others do it". Game theory says that all parties could be better off by co-operating but if you get benefit if you defect while others co-operate then everyone would end up defecting. See https://en.wikipedia.org/wiki/Prisoner's_dilemma#International_politics https://en.wikipedia.org/wiki/Prisoner's_dilemma#Internation... for an example.