Summary of Mr.Gerson's article: Vote for Secretary Clinton despite her lack of integrity and ethics.  Do not vote for Mr. Trump because of (fill in favorite demonizing epithet to describe your feelings towards him)
I agree with Mr. Gerson on at least one thing: both candidates are monsters.  But one of them unarguably will be inaugurated as President on 20 January 2017.  
If monsters cannot be destroyed, they must be leashed and contained. Consider the constraints that will be placed on Secretary Clinton and Mr. Trump whichever one wins the election.
Secretary Clinton will have a fawning media, a compliant political establishment and a court packed by her who have no regard for the Constitution.
Mr. Trump will be tracked incessantly by a hostile media, has no relations with anyone in the political establishment and, based on the list of judges he provided several months ago, will appoint judges and justices with a strong allegiance to the Constitution. He will have the biggest leash.