(CNN)I had the honor of serving as Ronald Reagan's White House political director from 1987 to 1989, so I can claim some insight on U.S. politics. My central conclusion on the 2016 race: It might not be entirely clear that Hillary Clinton deserves to win the presidency, but it is thunderingly clear that Donald Trump deserves to lose.
From this premise, I will do something that I have not done in 40 years of voting: I will vote for the Democratic nominee for president. The depressing truth of the Republican nominee is that Donald Trump talks a great game but he is the emperor who wears no clothes.
Trump falls short in terms of the character and behavior needed to perform as president. This defect is crippling and ensures he would fail in office. Trump is a bigot, a bully, and devoid of grace or magnanimity. His thin-skinned belligerence toward every challenge, rebuke, or criticism would promise the nation a series of a high-voltage quarrels. His casual dishonesty, his policy laziness, and his lack of self-awareness would mean four years of a careening pin-ball journey that would ricochet from missteps to crisis to misunderstandings to clarifications to retractions.