There's a long history of presidential untruths. Here's why Donald Trump is 'in a class by himself' (Los Angeles Times)

As president, Ronald Reagan spoke movingly of the shock and horror he felt as part of a military film crew documenting firsthand the atrocities of of the Nazi death camps. The story wasn’t true. ...
http://www.latimes.com/politics/la-na-trump-presidential-lies-2017-story.html