At one point, for example, [Donald Trump] argued that he knew much more than military leaders about the pursuit and defeat of ISIS. His assuredness of his own correctness seems also rooted in arrogance reflecting his fundamental insecurity. This insecurity and his belief in his own rightness, when combined with his success at making money, leads him to be self-reliant in his decision-making, which could result in his taking risks with threatening or using nuclear weapons.