Nixon is reviled as a failure by the US for what his administration did and every presidential scandal is post-fixed with 'gate' after the Watergate of his time. But what really angered the nation seems to be that he never apologized or explained himself ... until David Frost interviewed him. That historical interview, where you see the man, the genius that was Nixon, and his apology is what this movie is about. I ended up loving Nixon!:)
'Watergate' is a term used to describe political cover-up. The origin was a break-in at the Democratic office in the Watergate Complex to steal their candidate list. Nixon was away on holiday when it happened - though some say he was aware of it - but when he returned, his staff tried to pay off the perpetrators and unfortunately Nixon tried to protect his staff (which was the coverup). He couldn't see a good way out of the situation, and the congress went for the kill threatening impeachment. The snowballing mess ended when he resigned, the only american president to do so.
To me he came across as a wonderful man caught in a painful dilemma - loyalty, honour and responsibility shackled him to his fate. I know how people can gang up and the press can crucify an individual and that is what I believe happened to Nixon after watching the movie (and the original interview on youtube). David Frost with his genuine love of people brought out the human in Nixon, a proud, unreachable man, and made history.
[Keeping in mind that Nixon was responsible for the US napalming entire villages in southeast asia for a senseless war in Vietnam ....]