"We don't know which industries are going to be the ones that are going to do well in the future, and it's very difficult to retrain not knowing which industry or occupation you're going to end up in eventually," economist and University of California Haas School of Business professor Andrew Rose said
However, Silicon Valley may provide a direction with its shift toward green technology.
President-elect Barack Obama said he wants to create jobs that cannot be outsourced.
Hau Lee, at Stanford University's graduate school of business, thinks that green tech can do that. A leading expert in supply chain management, he believes creating clusters are the answer.
"Maybe it's time for us to think of this cluster, green tech industry as a cluster and think about the surrounding infrastructure, supply network, operations, and maybe the government can take the leadership to give the right incentives and motivate and incentivize the industry to be developed around the cluster," Lee said.
California is a major source of green tech ideas, responsible for 44 percent of solar and 37 percent of wind patents.
However, foreign inventers are registering more green tech patents than Americans. They surged ahead in 1998, and the U.S. has not taken back the lead.
"The new things that our new president wants to stimulate are happening here, our message to him from Silicon Valley is to continue to give us the tools to make it happen faster," president and CEO of Joint Venture Silicon Valley Russell Hancock said.
Mike Curran, head of the Valley's job training program Nova, agrees.
"We have the opportunity this time to bring all people to better jobs and better skill sets of jobs that are jobs in place that are more likely to stay here, especially the operation and construction of it, and jobs that will have the opportunity to have good wages and good benefits," Curran said.
If green tech is part of the Valley's future, some are saying 150,000 jobs could be created.