Suppose you were given control of the U.S. at the level of a “democracy” in Sid Meier’s civilization. That is, basically you can unilaterally sign off on whatever project you like, with complete control over the budget (so long as people are kept reasonably entertained, and you don’t start any wars.) What Wonders of the World would you build?
For purposes of this conversation, a WoW doesn’t have to be one from any of the Civ games. It’s just a big project, with a fairly well-defined but worthwhile goal. It could be an engineering triumph (a la the Apollo program) or a major scientific hurdle (the Human Genome Project- no big structures were built, not so much new technology had to be developed, but an enormous amount of data was collected.) I would suggest that in general a WoW has to be in some sense be “completionist.” i.e., “go to Mars” instead of “put more money in the space program.” “Sequence the human genome” rather than “give $500B to the NIH.” (Not a bad idea from where I’m standing, though. 
) Also, it should be possible with current or forseeable technology, like the state of space technology at the time JFK announced the goal of landing on the moon.
Let’s also assume that you have about $500B to work with. (That being the price of the S&L bailout from the nuclear rocket thread. For that matter, I think we can assume that we could cut back the military to a size that would fight four simultaneous wars instead of five, for example.)
Also, it doesn’t have to be a scientific/engineering breakthrough. For example, I would probably put some of that money into a vast national scholarship program, to make sure that any kid who can hack college will have the money to do so.
My own WoW would be a global water supply. I heard it said on the radio that it wouldn’t cost much to see to it that everyone in the world has clean water, if only there were the political will to do it.
Secondly, I’d have NASA build a satellite that would look for supernovae with a wide-angle spectrometer. Right now physics is in the state it was 100 years ago, you see. They thought that had it all tied up, and then they discovered radioactivity, and everything changed radically. Now, we’ve found that the expansion of the universe is accelerating, thanks to a hitherto unknown force called “quintessence.” Given the supernova observatory, we could get better measurements relating to quintessence, making possible a scientific revolution comparable to the one that gave birth to relativity and quantum mechanics.
While we’re at it, I’d also build a particle accelerator dedicated to making antimatter, to boost our burgeoning antimatter industry. Right now we have enough ability to make, transport, and manipulate antimatter that people are beginning to look at industrial and medical uses of the stuff, so it would be nice to bring the price down.
Fourth, I’d put enough money into ISS to do it right. Hey, with $500B, the least we can do is to add that missing escape pod, right? With that in place, the people on the ISS can actually do something other than… just run the ISS.
