Sure, why not reconstruct the solar system?

I found a reference to this Popular Mechanics article from 1952, "Shall We Move to Another Planet?" in Gregory Benford's new book,The Wonderful Future That Never Was: Flying Cars, Mail Delivery by Parachute, and Other Predictions from the Past. The article features astronomer Fritz Zwicky, who argues that humanity could re-engineer the solar system, using nuclear fusion as the power source, to make it more suitable for human habitation. Zwicky credits the problem-solving technique he invented, morphological analysis, for his insights.

For example, Zwicky says, we could send Mars into a new orbit past one of the gas giant planets to pick up more atmosphere, then have it return to its original orbit. (Humans would have to do some large-scale chemical engineering on the new Martian atmosphere so that they can breathe it, of course.) Or we could disassemble or shrink the gas giants to make new Earth-sized planets, stock them with suitable atmospheres, and then move them closer to the sun so that humans could settle on them.

You have to admire Zwicky for bold thinking, and he anticipated Freeman Dyson's later speculations about building some kind of megastructure around the sun to capture as much of the available solar energy as possible. If humanity ever gets into Kardashev Type II territory, it would have to consider this sort of engineering to meet its needs for energy and other resources.

No doubt Zwicky, who understood the physics involved as well as anyone, had performed some back-of-the-envelope calculations to show the plausibility of his ideas. His efforts reminds me of the proposals I've seen over the years for starships based on our current understanding of physics but also assuming an economy which has power levels at its disposal measuring several order of magnitude higher than ours. But as experience has shown, an idea for a new technology which looks physically doable on paper, or in a computer model, often runs into practical obstacles when we try to instantiate it in real engineering.

Ironically, these aspiring planetary engineers and starship builders admit that they can't deliver the goods today because the underlying support system won't exist for many generations, assuming exponential growth in humanity's power consumption and the mastery of nuclear fusion. Therefore we cannot test their ideas empirically for a long time, if ever.

These imaginary engineers therefore have a valid excuse for their inability to produce. Contrast their situation with a certain school of "nanotechnologists" dating from the 1980's who keep saying they can build some fantasy called a "nanoassembler" in short order, if someone would just give them enough money. They don't claim that they need some correlation of forces in a remote century, in other words. One, I don't see why they would need millions of dollars; and two, they've had almost 30 years to make the case for their project. Why can't they pull their act together, if the underlying idea makes physical sense and has merit?