"Estimates of the return on investment in the space program range from $7 for every $1 spent on the Apollo Program to $40 for every $1 spent on space development today."
Yes, because they are basically exercises in bullshit. You might think they went and catalogued in detail what the benefits were, but they're actually just based on macroeconomic assumptions about what the return on R&D is.
I mean, think: for spinoff arguments to work, you need to have some notion of how technology would have progressed without NASA. How could one possibly figure out that contrafactual?
It’s an engineering test platform for long duration space flight. Along with the development of reusable rockets we are now almost to the point of being ready to actually go somewhere and do more than just plant a flagpole.
Apollo was ridiculously ahead of its time and was not sustainable. The entire stack was disposable and it’s pure luck that we never lost a crew. We needed a project like the ISS to do the real work to figure out how to live in space and build long lasting space hardware.
The biggest shortcoming of the project is that we never tried centrifugal gravity. There were plans for a module but it never got there.
That's great, except (1) the thermal environment is all wrong, (2) ditto for the radiation environment, (3) that just pushes back the need for justification to long distance spaceflight. Justifications for space activities that amount to "enables other space activities" are an example of what's called a "self-licking ice cream cone".
There were plenty of non-self-referential justifications for ISS (like growing protein crystals, or space manufacturing) that never really went anywhere.
Ironically, maybe the best justification was it shows large space structures can be assembled from small units, so large launch vehicles aren't needed. NASA has of course totally ignored this lesson with SLS.
It's really hard to put a dollar value on what the value of having something like SpaceX Starship available is, and it's hard to evaluate what the Starship project would look like if we hadn't put the money into the Apollo/ISS/STS/SLS before.
With the current state of things, I would bet that with a fully reusable orbiter like Starship, space-based solar with microwave transmitters will probably be a cheaper option than fusion. But we should work on both because we can't predict it until both are tried. It's easy to say no to a project when we don't know what the outcome will be, but we need to take on a lot of big risky projects to see which ones give outsized returns.
SLS only started in 2011. If SpaceX learned anything from it, it was not much and it was after they'd proven themselves. Starship has been quite from-scratch outside of the engines.
I mean, SLS was definitely a waste of money, and arguably so was STS. But that's easier to say in hindsight, and it's also easy to say in hindsight that SpaceX had an obviously better approach, but that was harder to support in 2011.
Oh, I think plenty of insiders were calling STS a waste in foresight. I recall a story (no source, sorry) that one of von Braun's people lamented about it: "they've reinvented the wheel, and made it square." Minimum Cost Design methodology for launchers dates from the 1960s.
