Aside from the need for more stimulus, I don't think it's crazy to suggest that the US has underinvested in public infrastructure in recent years, and private investment was horribly misallocated towards real estate projects. A lot of public infrastructure isn't very exciting - things like fixing sewer systems - but still necessary.
They Insituformed the sewer on our street this week. Vivian thought it was pretty exciting, especially the steam coming out of the manholes last night. Combine that with the summer long project to remove the lead water lines in the neighborhood, and there's been a lot of machinery to entertain a toddler -- and stimulate the economy.