I came across this description of a Head of State as a child, age 12: "He is very arrogant, extremely smug and quite taken with himself...is offended at the slightest comment, plays the injured party and more than occasionally gives an impudent answer; furthermore, he is unbelievably lazy and slovenly."
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Sounds like someone we now know, but in fact the description is of the future Kaiser Wilhelm II, from his MOTHER, Queen Victoria's daughter Vicky. Wilhelm's character would later be seen as a major cause of WW I.
Trumps personality deficiencies and militarism seem to present a grave danger of history repeating, except the death toll could be in the billions this time, as opposed to WW I's millions. It's ironic that some still repeat the fantasy that he was the 'peace candidate' compared to war-mongering Hillary.