A recent story on Marketplace about the housing market, makes the claim that until the housing market recovers, the economy won't recover, and there are plenty of problems with the housing market which can sabotage an economic recovery. This story does not address the whole issue, by any means, in my opinion.
Here is something to consider:
1.) The US economy (and the global economy as well) is presently in the toilet because the "engine" which drives the US economy (housing and the financial markets) has collapsed.
2.) "Monoculture" farming (i.e. growing one type of crop) is generally recognized as a Really Bad IdeaTM because if anything happens to the crop (And monoculture crops are exceedingly vulnerable to disease. Ask the Irish or banana farmers.), then your entire economy will implode.
3.) The efforts at restoring the US economy are primarily focused on "correcting" the problems with the system and not ensuring that other industries play an equal role in driving the US economy. (We'll prop GM up, but we're not looking at putting other industries in Detroit, even though many of the jobs that have been lost at GM will not be replaced once GM is out of government control.)
4.) Putting boatloads of money into the space program helps create a diverse economy and can put many of the unemployed autoworkers back to work (the machinist who made car parts can make parts for a spaceship just as easily).
5.) The spin offs from the space program have lead to things like improved fire retardant gear, medical devices, and the like. The spin offs from the financial sector lead to Collaterialized Debt Obligations, ARMs, and the like.
6.) Having a large high tech industry attracts highly educated people to the US (who tend to make a lot of money), which adds to the economy and the tax base. Many highly educated folks are leaving the US to go to work in India and China, because the opportunities are greater there, even if the money isn't. If we put more into the space program than anyone else, a lot of those people will be inclined to stay in the US (since they're not likely to work on a manned mission to the Moon/Mars in India).