Historically, large-scale global trade has served two functions: 1) the exchange of goods between willing sellers and buyers described in Econ 101 textbooks; 2) as a tool of state aggrandizement, in which the private parties are stand-ins for governmental interests.

Compared with U.S. cities, Japanese cities bend over backward to help foreigners. The countryside is another matter.

A whole bunch of big technological shocks occurred when Asian innovations - paper, gunpowder, the stirrup, the moldboard plow and so on - came to Europe via the Silk Road.

A smartphone links patients' bodies and doctors' computers, which in turn are connected to the Internet, which in turn is connected to any smartphone anywhere. The new devices could put the management of an individual's internal organs in the hands of every hacker, online scammer, and digital vandal on Earth.

A world with a sudden limit on air travel would be tremendously different from the one we live in now.

The embrace of a new technology by ordinary people leads inevitably to its embrace by people of malign intent.

Historically, large-scale global trade has served two functions: 1) the exchange of goods between willing sellers and buyers described in Econ 101 textbooks; 2) as a tool of state aggrandizement, in which the private parties are stand-ins for governmental interests.