BOOM times are back in Silicon Valley. Office parks along
Highway 101 are once again adorned with the insignia of hopeful
start-ups. Rents are soaring, as is the demand for fancy
vacation homes in resort towns like Lake Tahoe, a sign of
fortunes being amassed. The Bay Area was the birthplace of the
semiconductor industry and the computer and internet companies
that have grown up in its wake. Its wizards provided many of the
marvels that make the world feel futuristic, from touch-screen
phones to the instantaneous searching of great libraries to the
power to pilot a drone thousands of miles away. The revival in
its business activity since 2010 suggests progress is motoring
on. So it may come as a surprise that some in Silicon Valley
think the place is stagnant, and that the rate of innovation has
been slackening for decades. Peter Thiel, a founder of PayPal,
an internet payment company, and the first outside investor in
Facebook, a social network, says that innovation in America is
“somewhere between dire stra