The author takes a fascinating subject and manages to make it dry and laborious. The information is very interesting; the prose will bore you to death. The section on Somalia at the end picks up somewhat, but if that's your main interest I recommend Mark Bowden's far superior Black Hawk Down.
Still, I learned a lot by reading it. The section on Robert's Rangers (and the often-false mythology thereof) in particular has stuck with me in the many years since I read this.