"Make America Great Again" is the oft-caricatured slogan of the Donald Trump presidency. When Trump was elected, he boasted of jump-starting the economy to achieve an annual economic growth rate of 4 percent.
Experts laughed him off as a naif who did not understand that structural changes in demography and technology made such growth impossible. Many economists predicted that Trump would crash the stock and job markets.
Yet less than two years into Trump's presidency, the economy achieved 4 percent growth in the second quarter of 2018. Unemployment rates are at near-record lows. The stock market and oil and gas production are reaching unprecedented heights.
Such radical turnarounds have been common in U.S. history. As the ancient Athenian historian Thucydides noted, large democracies are by nature volatile, they can mobilize quickly, and they can change on a dime -- sometimes in the right direction.
In late 1983, Ronald Reagan was being written off a practitioner of voodoo economics. The country was still mired in a recession caused by Reagan's efforts to break runaway inflation.