This turnaround shows just how fast things turn

U.S. history, largely because the economy had been reinvented almost overnight from a bust to a boom.

In 1940, Depression-era America was recovering from yet another downturn. The New Deal had not restored prosperity after the 1929 crash. Europe was largely under the control of Nazi Germany. Only the United Kingdom was left of the European democracies that had fought Hitler. The Soviet Union was aiding Hitler. Imperial Japan was preparing to gobble up most of the Pacific, especially orphaned European colonies rich in oil, rubber, agriculture and precious metals.

The United Sates was torn apart politically between isolationists and interventionists. Fights broke out in Congress over whether the country could afford to rearm. The U.S. Army was smaller than Portugal’s. In almost every area of armament, America was far behind the armed forces of the Axis powers.

Then the world again flipped upside down.

After Pearl Harbor, the United States engineered the greatest economic expansion in history. Within four years, the U.S. economy was greater than that of all its enemies and allies put together.

The U.S. Navy had become larger than all the navies of the world combined by 1944. A once virtually unarmed America now had more military aircraft than Germany, Italy and Japan combined.

A war that in early 1942 looked like it might either go on for years or end in an Axis victory was over less than four years after the U.S. entered the conflict. The Axis powers were not so much defeated as ruined.

Pundits should be careful with their sure-thing predictions, especially in the matter of a powerful, unpredictable and explosive America. With the risk-taking and unconventional Trump, and the hysterical opposition to him, we are entering another unpredictable and volatile era in American history.

Radical and unexpected economic recovery can happen at home and abroad. Such fundamental change in the status quo can swing the November election — quickly and in unforeseen ways.