It's funny that he thinks there's a market for his wisdom so soon after his judgment was widely repudiated by most of the country--everyone except a rump within his own party. It's not my judgment, it's that of book agents who told him to "wait awhile" until, like his role models Truman or Nixon, his reputation has unsoured enough to provide an opening for his wisdom.
What does "his wisdom" have to do with anything? He was probably the most important person in the world during the last eight years, and is one of the most controversial figures in recent history. You don't this book is gonna sell like crazy?