I'm glad I didn't know anything about that backstory when I started reading it. It opens with two boys on a camping trip, hiding in a farmer's barn, when they hear the thumps of an oncoming tripod. They watch as it snags and captures the fleeing farmer, whips the family dog into the ground and destroys the farmhouse. Then the military comes and quite easily destroys the tripod when it tries to lift the tank. Later, the boys learn that 3 other tripods had landed on the planet and they were all easily destroyed. The tripods become a bit of a laughingstock (emphasis is made on how awkward they look when they walk). There is even a TV show for children, which starts to become quite popular, even amongst adults.
Things start to get weird when the protagonist notices how angry his sister gets when he forgets to record an episode of the Trippy Show. She completely loses it. Soon the Trippy show starts spawning a social movement of people called Trippers. They start to migrate out of cities and gathering in large groups in the country (mimicking a hippy movement in some ways). Again, I stop going into any more detail, because the deliciousness of the book is how the Tripod conspiracy unfolds. Even in a fairly short young-adult novel, Christopher's very dark view of mankind comes through and he is extremely effective at creating the atmosphere of real dread when a previously open society starts to tighten things down.
It's a very quick and entertaining read and definitely worth it if you have read the original trilogy.