But full credit goes to the company where Mr. Taylor worked after leaving ARPA: Xerox. It was at the Xerox PARC labs in Silicon Valley in the 1970s that the Ethernet was developed to link different computer networks. Researchers there also developed the first personal computer (the Xerox Alto) and the graphical user interface that still drives computer usage today.

According to a book about Xerox PARC, “Dealers of Lightning” (by Michael Hiltzik), its top researchers realized they couldn’t wait for the government to connect different networks, so would have to do it themselves. “We have a more immediate problem than they do,” Robert Metcalfe told his colleague John Shoch in 1973. “We have more networks than they do.” Mr. Shoch later recalled that ARPA staffers “were working under government funding and university contracts. They had contract administrators . . . and all that slow, lugubrious behavior to contend with.”

So having created the Internet, why didn’t Xerox become the biggest company in the world? The answer explains the disconnect between a government-led view of business and how innovation actually happens.