While reading Chosen Soldier, there was a reference to the book Masters of Chaos as a good historical account of the missions of the Green Berets over the past 20-30 years. This sounded interesting to me so I put it near the top of my list.
Masters of Chaos presents a brief overview of the history of the Army Special Forces, followed by a more in depth look at the major conflicts they have been involved in since roughly the late 1980s and continuing through the early 2000s in Iraq. The breakdown of how SF was used in each of these conflicts gives one a decent idea of how SF operates. It is clear where their strengths and weaknesses guide many of the actions that they participate in. Clearly this work only covers a subset of the different teams and groups during different conflicts, as well os only really covering actions taken during known, overt wars and missions. But the general picture of fighting by, with, and through foreign allies is overwhelmingly clear.
I also found this book gave a different perspective on the conflicts themselves. There are definitely entire books dedicated to each of the conflicts the US has been a part of over the past 30 years, but this gives a unique perspective through the eyes of the SF soldiers on the ground. I found it to be an easy read, although it was a bit disjointed at times seeming like a collection of stories rather than a wholly coherent narrative.