I am sure he has a mental disorder...we are in for a rocky ride if this man gets into the oval office.
In Donalds case is would be called Delusional Grandeur
WIKI
Delusional Grandeur characterized by fantastical beliefs that one is famous, omnipotent, wealthy, or otherwise very powerful.
Delusions of grandeur are a subtype of delusion that occur in patients suffering from a wide range of mental illnesses, including two-thirds of patients in manic state of bipolar disorder, half of those with schizophrenia.