So many books (you know the rest)
This book is by the most fatal sniper in the American military, who excelled at his duty. His chapters are open and honest, and he talks often of how his military calling conflicted with his family duties. His wife also narrates short chapters here and there.
You learn of his childhood and what sort of person he was before becoming a SEAL. You also get a sense of what the training was like during the different phases of his career.
What makes it all most interesting is how Kyle felt about the kills and what sort of toll it did or did not take on him.
Sadly, he was murdered shortly after the book came out by a veteran he was trying to help.