I think if we were looking for someone to compate to Hitler, we'd have to find someone , perhaps a vet with a history of loafing around living off of his family and discovering politics and racism.  He would then help organize a failed coup, do some time in prison then lead a series of elections resulting in his appointment (not election) to a very high ranking office which will lead to the presidency.  

Trump shows a lot of bigoted, ignorant and megalomaniacal tendencies but a Hitler?  Nope.  Perhaps a better candidate would be someone who achieved high office and sidestepped our laws to consolidate power.  Perhaps even lead us to war on false pretenses.  Hmm.