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I remember reading it in mid-to-late 90s. It was a hardcover with a huge starship drawn on the cover.
The plot was about humans making first contact with a new alien species, when aliens suddenly attack and quite easily destroy the entire fleet. Only one survivor is taken prisoner to the aliens' homeworld, where he is being prodded, tested, and evaluated. The survivor happens to be a son of some important general who sends an elite force of commandos to rescue him. In the meantime humans are preparing for the inevitable invasion.
The ending seemed open, as if this book was part of a set. Seems like I may be missing closure to this story.