The Chinese stock market is plummeting so fast that authorities there keep shutting it down. North Korea set off a bomb in a nuclear test. Two of the Middle East’s great powers, Saudi Arabia and Iran, are eyeing each other menacingly. In the European Union, political extremists are on the rise, migrants are pouring in and Britain may drop out (three phenomena that are not unrelated).

And in the United States, the number of people filing unemployment claims is hovering near the lowest levels in four decades, the jobless rate may well fall below 5 percent for the first time since 2007, and whatever the noise on the presidential campaign trail, Congress recently passed bipartisan legislation to keep the government running comfortably into next year.

Seven days in, 2016 is shaping up to be a chaotic year in global economics and geopolitics, with profound challenges nearly everywhere. Except, for now at least, in the world’s largest economy. The American economy is acting as a steadying force in a volatile world.

A giant question for 2016 — not just for Americans but for people across the globe who benefit from having one of the world’s major economic engines revving while others sputter — is how resilient the United States will prove to be.