Multitudes of characters, converging plotlines, cold war intrigues, and a good old fashioned, worldwide alien invasion story. There's good and bad in this novel, but at the end, the good outweighed the bad and made the book worth reading. I'll start with the bad, and get that out of the way-
Too many characters. They become hard to keep track of after awhile, especially when you have to also figure out social connections that appeared briefly pages ago.
The invading aliens look like...baby elephants. It ends up working, but for me it was a serious distraction for quite a bit of the novel. Not how I would picture aliens, and making something so strange and foreign resemble any known animal is going to imbue the characters with unwanted stereotypes.
Like "Lucifer's Hammer", another story by the same creative team, this book is a bit slow to start (although I enjoyed most of the buildup, something too many modern tales lack). The middle starts interesting, becomes a compulsive page turner and then...it just ends. Yes, there is a resolution. No, I don't need every string of a storyline followed to a conclusion. But, a little bit more? The kiss goodnight? That would have been appreciated.
Some of it feels a bit too neat and tidy. The alien spaceship has technology on it that is too similar to how humans would build something. This is an alternate race from another galaxy. I would expect their trappings to be more...alien. The way they invade the US, and the way they conduct parts of their invasion, is also too human.
The well researched details of a world wide response to the invasion.
The clever way the aliens have inherited their technology, are a younger race, and have more of the social structure of herd animals than humans. In fact, the way they react with confusion towards the humans and their unique characteristics is a strong point.
The lengthy focus on background and character developement-something too often jettisoned in the modern rush to quick action.
The way several disparate elements merge into a workable, believable resolution.
So, the book was worth it, is a keeper on my bookshelf, but isn't exactly a classic.