All US presidents lie except maybe for General Washington and John Adams, and they are suspect. Lincoln was one of the best presidents and one of the best liars. That's why they called him 'Honest Abe'. Kennedy literally saved the world from nuclear disaster, but he could lie with the best.
Hey, I like some things about Donald Trump, but I don't know the man. What I do know is he's never been poor, and to me that means he cannot possibly be completely grounded in reality. He's never even had the opportunity to experience failure. There is no walking the line for him, no oxygen choices, no dying from making a mistake.