Personal history time; I can recall vaguely some of the circumstances surrounding the tale told in Osprey Raid #24: The Last Boarding Party: The USMC and the SS Mayaguez 1975; it was the year I could have been drafted, but though they'd pulled our numbers, the Armed Forces didn't call anybody up. The very next year, no numbers were pulled, and the draft was essentially over.
Anyway, the book.
It deals with the period of the winding down of US military involvement in SE Asia, when the Khmer Rouge chose to dabble in high seas piracy, and the US response to same. The book goes into detail about the good and the bad of this raid, leading to the return of the US flagged ship.