For the past two decades, the nation's unprece-dented economic boom has been driven in large measure by the computer industry. But many experts believe that further high-tech innovation will stall if engineers continue to rely on silicon-based microprocessors, which have limited computational capacity. Other futuristic technologies -- including molecular processors and quantum computers -- are being developed that promise radically better performance. But some industry experts warn that several non-technological roadblocks are also thwarting the pace of advancement. They say vital government funding for research into new technologies has steadily eroded, that the number of U.S. science graduates has plummeted, resulting in a shortage of talent, and that U.S. immigration policy doesn't admit enough foreign computer experts.

Patrick Marshall is a freelance writer in Seattle, Wash., and contributing writer for CQ Researcher who writes about public policy and technology issues. He is a computer columnist for The Seattle Times and holds a BA in anthropology from the University of California at Santa Cruz and a master's in international studies from the Fletcher School of Law & Diplomacy at Tufts University.