I admit to despising Mr Nixon, the worst president in US history, but though I lived through his entire career from Ike to Watergate even I could not accept the depth of his lunacy in this otherwise quite well done alternate history. Nixon was a liar, a thief, a man willing to throw anybody at all under the bus to save himself, but that's likely true of 80% of all US politicians who reach or at least come close to the presidency.
What did seem realistic was the circus going on around him and his office. Power crazy men like Tricky Dick attract others with the same goals. And those people are not restrained by any oath of office as they don't take one. It's easy for them to go step by step into territory they never intended to reach when they set out.
It was a good story, well developed and worth reading, but even Tricky wouldn't have gone quite as far as the author took him.
On the other hand, some reviews are even more entertaining, "left wing politicians", "liberal biased media", did not destroy Nixon. He did it to himself, and everybody could see it coming, for years and years.