I think the people around him believe (1) he's competent to win the popularity contest that is an election & (2) he's vengeful against any perceived disloyalty.

There are probably some true-believers among his cabinet, but most of those are evidenced by their paper-thin CVs and lack of their own power-bases (Hegseth, Bondi, Rollins, Chavez-DeRemer, Turner, McMahon, Noem, Zeldin, Loeffler).