The most mind boggling part of this book was the way in which the soldiers traveled. This book was written a hell of a long time ago, so much of what we know about physics would probably make Haldeman's plan for interstellar travel pretty much impossible, but regardless here it is. They pass through things called "collapsars", which are essentially black holes. Since it is impossible to reach the speed of light, one can go through a collapsar and appear somewhere on the other end. The thing about traveling this way is that for those inside the collapsar, people practically going the speed of light, experience a completely different speed of time than those outside. Mandella might experience a week on ship time, while the Earth would experience years. Centuries pass him by like nothing. What I found interesting was actually trying to contemplate running a military with this sort of time dilation. How does one schedule someone for deployment when you haven't a clue when a ship is going to be coming back in? This was the one thing that just made it so amazing for me.
I think this is an amazing novel. It's not the best written SF novel I have read though. Haldeman is rather good at writing, but his style is not as strong as Scalzi's, in my opinion. However, this doesn't in any way detract from the effectiveness of the novel. I found myself caring about what happened to Mandella, and alternately what happened to his friends. He is able to draw that sort of emotion with me in his writing.
Haldeman makes the changes on the Earth over centuries look so real and natural. You start to wonder how you would react to a world that is so drastically different. What do you think you would expect if in two hundred years the Earth was overpopulated and there was need for some sort of universal birth control?
This book is essentially a classic. Everyone should read it at some point in their reading life. It's a relatively quick read and delves deeply into an ever changing world that you start to feel a little out of place. If you read this, think how you would react to a world so drastically different from your own? Would you be able to adapt to the changes? Or would you try to find a new home for yourself?