This is an Omnibus version of the novels Forever War, Forever Free and Forever Peace.
Joe Haldeman was drafted into the Army and served as a combat engineer in Vietnam. Forever War was inspired by his wartime experiences.
William Mandela is conscripted into the United Nations Exploratory Force (UNEF) for a war with the mysterious Taurens. The training is gruelling and realistic, the recruits don’t die like flies but it is close. The aliens where discovered when they started attacked human colony ships, that is at least the official truth. UNEF is being sent out for revenge and information. Their first target is an alien colony, which turns out to be unarmed. Their first fight is a walkover but they fight many more battles and they aren’t as one sided.
You need a little info dump. Travel in this universe is done between collapsars at time-dilated near-light speed.
Much of the book deals with the problem of fighting a war restricted by this. When the soldiers return to Earth they traveled hundreds of years into the future, and society on earth have changed, sometimes in fundamental ways. The returning soldiers suffer from Future-Chock every time they return.I believe that is in a way related to what Vietnam veterans felt when they returned home.
But the time dilation have other problems, it affects the tech level of the soldiers, they never know if the aliens they are going to fight is from their own future with higher tech or not. Mandela survives it all and he is soon the oldest surviving soldier.
Good books often have a love story, this one is William and Marygay’s. They serv togheter, but they eventually gets out of the military and has to handle a very different society where overpopulation and famine has lead to wars and the World Government encourage same sex relationships. Many of the soldiers become alienated by the many changes to society and reenlist even if its a choice between bad things, at least they will be with people more like themselves. So Will and Mary goes back to war only to be sent to different units.
William is a reluctant soldier, even though he advances to commanding officer of a taskforce. He can’t really relate well to his soldiers, they are from a different time, speaking a differnet language and they all are gay. They fight with medival weapons inside a forcefield that stops more advanced weapons.
While the war contines humanity developes into MAN, clones sharing a hive mind. MAN can finaly communicate with the Taurens and reach a peace agreement.
MAN keep hetero-sexual colonies on a few planets as a genetic insurance. That’s where Marygay and William end up, finally togheter.
This takes off a few years after Forever war, Williams and Marygays are married and live on the planet Middle Finger (yes). They eventually become frustrated with society and want to jump forward in time again using a space ship.
They bring their daughter and leave their son, who is joining a post human hive mind. They dont get far before a peculiar phenomena stops them from going farther. When they return to the planet, it is empty of people. The mystery is daunting.
They eventually travel to earth and finds it empty too. They meet a very strange shape shifting being there masquerading as an android. He doesn’t know where all the humans are.
The ending is very Deus Ex Machina, it didn’t leave me as satisfied as Forever War.
This isn’t really a sequel to the two others. It takes place closer to our time. War is fought by soldierboys, jacked up soldiers sitting in bunkers at home driving the war by remote. The rest of the population can jack in and enjoy the war.
The soldiers share minds with each others while jacked in. It creates a deep bond between them. It also creats an idea for peace.
The last part of the book is about ending all wars forever.