 I read this book when it first came out and I remember being floored at how good it was. I mean, Silverburg can be hit and miss. This was a hit. The story is about these bizarre, powerful aliens who show up on Earth one day claiming to have the best of friendly intentions, but very quickly showing that they came here to take over. The story is very large and sweeping in scope. It spans a couple of generations and we watch how people learn to cope with this alien occupation. The aliens apparently thought it would be easy. If you're not seeing the political and social parallels here, then I can't help you.