Problem is there's no manufacturing here laying idle and, what's more, there no striking, earthshaking innovation or invention on the horizon to move the economy forward. Those were two elements of promise present even during the "Great Depression." Those elements don't exist today. That's why it is much different in today's poor economy than it was in the 1930s. Read an article on this very thing just a few days ago, though, unfortunately, I'm unable to recall the source.
Establishing energy independence would be a great place to start with job creation in the private sector. Converting our transportation to natural gas would be a major contributor. Drilling for domestic oil on shore and off would be significant. A major effort in nuclear power for electricity would also create many jobs. Develop clean coal technology and wind and solar would be second order job creators but important for the longer term (20 to 50 years out). In addition to policy changes in Washington we need massive regulatory changes to allow energy independence to happen.
Or, we can continue on course giving billions to green pie-in-the-sky political donors. Sheesh.