Economists have long argued that it's very hard to build your way out of traffic congestion--regardless of whether the building means adding lanes to roads or adding mass transit. The fundamental issue is that many of the people commuting to work have three adjustments they can make: some of them can adjust the time they choose to travel; some of them can adjust the route they travel; and some of them can adjust the method of their travel (single car vs. carpool, car vs. mass transit, and the like).
A large share of the concern over China's effect on the world economy starts with large Chinese trade surpluses. But in the first few months of 2018, China's trade balance was negative (using the standard broad measure of the current account balance). That is, China had a trade deficit, not a trade surplus. For example, the Economist magazine reports: "China’s vanished current-account surplus will change the world economy" (May 17, 2018). The South China Morning Post reports: "China’s first current account deficit for 17 years ‘could signal fundamental shift" (May 4, 2018).
Warren Buffett is of course as the golden-touch investor who is chairman and CEO of Berkshire Hathaway. Each year he writes a letter to his shareholders, and along with an update on just what the firm did the previous year, he often discusses some broader point. In the last couple of years, Buffett's annual letter has harked back to a revealing bet he made 10 years in December 2007.
With all the controversies over the US imposing tariffs on steel and aluminium, it's perhaps useful to consider an overview of what import restraints the US economy already has in place, and what effects they have had. Every three or four years, the US International Trade Commission publishes a report called: "The Economic Effects of Significant U.S. Import Restraints." The Ninth Update came out in September 2017. The report notes:
The rate of US teachers leaving for other jobs is on the rise. Adam Grundy of the US Census Bureau reports in a short note (May 2018):
Could vaping and e-cigarettes reduce the toll of death and illness due to smoking conventional cigarettes?
UK productivity – output/hour has risen 1.5% in a decade. Unemployment, at 4.2%, is the lowest since April 1975. Real-wages have risen by 1.1% per annum over the last four years. Robots may be coming but it’s not showing up in the data.