This is a story of the early period of Earth's interstellar exploration and exosapient contact. We have all the elements of a very good early Heinlein here:
- Powerful but limited faster-than-light travel (though not so fully explained)
- Earth governments cracking under strain, thus a secret organization (named ISIS!) emerges to steer Earth down the right path in confronting the aliens.
- A "true polymath" of a hero--investigative reporter, capable fighter, upstanding citizen to a fault. And a hunk/ladies man to boot. Named Caine Riordan. How many action heroes have been named Riordan? I think it's a lot.
- Really awkwardly portrayed women/sexuality.
It's not a terrible book. Caine generates interest once in awhile, and the diplomatic chess games are somewhat interesting. But this is 2014. I looked for any sense of understanding of how we've changed since 1963, and found none at all. Yes, the book asserts that women are the equal of men--you can find that in 1963 SF too, though the writers mostly didn't fully understand what that meant. There's no consciousness at all of how technology has changed us socially--it's early 60's mentality with spaceships.
I can see the award nominators' nostalgia in offering this up. But really, if you want this sort of thing, go back to the originals. Read Heinlein, Arthur C. Clarke, Asimov. Don't bother with this one. 2 stars from me.