Or is the problem that each incoming administration wants to rejigger the programs? If each president (thinking about Bush and Obama) would just hand the scientists and engineers a few billion dollars and tell them "go do something that'll make America proud," we'd have something to be proud of by now.

The Presidents don't have the final say in how much money each agency gets and how many Congressmen get a shiny new NASA facility or contract in their district. The slice of the budget that the executive branch has the authority to allocate is miniscule compared to debt payments, entitlements, and military spending.

NASA's problem isn't really the money, it's the ridiculous bureaucracy and systemic inneficies that inevitably occur when you are forced by opportunists to fragment your supply chain and distribute your engineering infrastructure across the entire country. The constant change in executive policy is a consequence of NASA's inability to achieve its potential in the face of a functionaly hostile legislature.

The same systemic problems caused the loss of Challenger: the reason why SRBs were segmented was that they had to be transported over rail from another state, instead of over barge from a nearby factory.

Arguably the loss of Columbia was also partially caused by the same systemic problems: shuttle had wings (instead of a lifting body shape) due to Air Force's wishes. IIRC this necessitated the existence of the ET.

We'd still need someone to provide a singular vision and focus. Human nature says you can't just throw money at a group of people and expect that to happen on its own.

100 times this. Providing "stupid money" but no vision and no accountability leads to the "but 4 billion of the budget needs to be spent in MY state - but then we'll have to transport the boosters by train - but then we'll have to cut them apart - but then we have to use complex o-ring seals instead of simply welding them together -> Challenger blows up" bikeshedding of the shuttle era.

I wonder if you think the vision needed to advance science is stronger among NASA scientists or US politicians.

Yeah, Bell Labs never did anything really important.

Actually it's scientifically been shown that you can just throw money at people. However, that study was not conducted on scientists, whom I am certain will squander it as they do now.

Without commenting on the relative merits of Apollo vs the Space Shuttle programs, it bears remembering that there were 11 Apollo flights and 135 Space Shuttle flights. There simply aren't enough statistics to know whether the Apollo flights were more risky than the Shuttle flights or not, and hence which program did the most to "limit progress in the name of eliminating risk".

One may criticize its progress for being slow, but what is beyond debate is that the Shuttle program did not anywhere near eliminate risk.

NASA doesn't have a champion, if they do this person is not enough to spark the public interest. That takes it off the minds of the majority of Americans. Worse with regards to politicians supporting NASA doesn't really garner them many votes so they allocate money into areas that will.

We need a dreamer who can connect to the public in such a way that politicians support NASA. The issue is, what is good enough and reasonable enough of a dream to accomplish? I think a permanent base on the moon that suggests one day civilians will be able to go might work but it will be a hard sale