There's this book titled "The Winged Gospel" about the aviation utopianism of the 1920's. At the time, these folks thought that private plane ownership would become as common as automobile ownership. This conveniently ignored the fact that piloting a plane is much more difficult than driving an automobile. Ultimately, the aviation utopian factions turned on each other.

None the less, aviation did develop, but not as private plane ownership. Instead, it turned out that commercial airliners and aircraft for defense were the neccesities which drove it.

Someday, someone will write a book about the space utopianists of the late 20th century. These folks thought that Mars was an Earth-planet, one that could be easily settled by people. They conveniently ignored the facts that Mars is not Earth-like, and that space travel is quite difficult and expensive. Ultimately, the space utopian factions turned on each other.

None the less, manned space flight will develop, but not as manned Mars flight by the masses. Instead, it will turn out that defense against asteroid and comet impact, and comparative planetary science, will be the necessities which drive it.

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