AmsterdamVallon

This article has some additional information:

As a former military intelligence instructor who helped America's elite Navy Seals develop their hand-to-hand combat techniques, the San Diego-born 45-year-old has spent two decades learning about violence.

And this:

The father-of-one joined the US Navy in his teens and missed out on graduating as a Seal following a diving accident which lacerated both his ear drums. Instead he joined military intelligence, and began working with the Seals on developing their fighting techniques.

So it sounds like he would have been a SEAL if not for a diving accident.

I can't remember if you've ever answered this elsewhere but what's the best book you've read this year?

"English merchant-turned-pirate," I'm not familiar with Bannister: What was the motivation behind turning from legitimate merchant to pirate?