I first read "Cities in Flight" back in the 70s. I agree with some of the other reviewers that the plot, characterization, and consistency of the novels was flawed--so I won't rehash those points here. Despite this, I thought Blish came up with a rather novel and breathtaking vision of the future. I was also struck by the political forces that created the Okie culture. Specifically, I was intrigued by the idea that the pressures of the Cold War was slowly forcing the US to become as totalitarian as the Soviet Union. This political transformation would serve as a prelude to the creation of a world-wide, Bureaucratic (socialist) state. According to Blish, this global entity resulted in repression and permanent economic depression. The only way to gain freedom was to use spaceflight to leave Earth behind. As a result, the State deemed spaceflight technology because it provided an escape route. Despite these restrictions, the technology was rediscovered and whole cities took the opportunity to literally lift off into space. Eventually, this trend caused the Bureaucratic State to collapse of its own weight. With the Soviet's losing the Cold War and democracy breaking out all over in the 80s & 90s, it seemed like Blish's political predictions would remain in the realm of fiction.