A Step Farther Out is a collection of non-fiction essays that Jerry Pournelle published in a Sci-Fi magazine back in the 70s. The essays were originally about whatever cool science topic that Pournelle wanted to cover, but when collected into a book they were sorted by theme: futuristic utopias, space travel, random weirdness, energy, etc.
Reading old non-fiction, especially non-fiction that's intended to be predictive, is kind of weird. You get to see all these things that people used to be worried about. Many of the essays in this book are arguments against various catastrophes that people worried about 45 years ago. Things like overpopulation, running out of energy, etc. What's funny is that many of the predictions Pournelle argued against said that there would be world-wide collapse before the year 2000. Now we're well past that point, but people are still worried about the same stuff.
Pournelle does worry about ecological collapse and running out of energy, he just thinks it will take longer. He also thinks that we have the opportunity, right now, to invest in R&D to open up an amazing future. If we do the wrong thing (business as usual), then he thinks we end up back in the muscle power world. If we do the right thing (invest in fusion and asteroid mining), then we get the glorious sci-fi utopia future.
Pournelle's rose-colored glasses are more convincing than most. For one thing, almost every chapter is full of Fermi estimates about how much it would cost in investment, time, energy, to do the things he suggests. For another, he continuously hedges by saying "we can have it if we try for it."
You can easily tell the essays written earlier from those written later. Pournelle is more optimistic in the earlier essays. By the later essays, he's watched some of his favorite R&D projects get cancelled by people who literally *want* to return to muscle power. By the end of it, he seems distraught that society as a whole is abandoning the glorious future. He warns us that if we don't invest in R&D now, our grandchildren will curse our names. I find myself agreeing with him.