From one of my readers: The Plundering of NASA: an Expose, How pork barrel politics harm American spaceflight leadership. You can buy the ebook edition here, and the print edition here.
I just finished reading it. Boozer’s introduction and opening two chapters provide one of the best detailed summaries explaining clearly why the United States today cannot launch its own astronauts into space, and why we are threatened with the possibility that we won’t be able to do it for years to come. And while his perspective is mostly from an engineering perspective, he also gives some of the political background behind this situation.
His later chapters are not as effectively written, but the opening is still worth it.
I will give a hint about his thesis: it involves comparing the Space Launch System (SLS) with private commercial space. And SLS does not fare well.