History is interesting, author David McCullough has observed, because things didn’t have to turn out the way that they did; they might have gone the other way.

McCullough’s wise observation comes to mind today because of an important anniversary.

Seventy-one years ago today, on Dec. 7, 1941, Japanese planes attacked the U.S. naval base at Pearl Harbor, Hawaii, launching America into the cataclysm of World War II.

We now know, of course, how that war ended. Thanks to the valor and sacrifice of millions, America and its allies prevailed over the Axis powers of Japan, Nazi Germany and Italy.

But on Dec. 7, 1941, the outcome of World War II was far from certain. To get some idea of the anxiety and terror touching Americans on that fateful day, we’d suggest that readers visit an interesting website curated by the Modesto Radio Museum. At the website, http://www.modestoradiomuseum.org/radio%20reports%20pearl.html, readers can sample various radio broadcasts reporting on the carnage at Pearl Harbor and its aftermath. Note the confusion of the reporting, the speculation, the shock of the broadcasters, the frantic search for answers that, on that day, were in short supply. The tenor of the broadcasts reminds us of the news that gripped America on another terrible day in our history — Sept. 11, 2001.

To hear the radio reports from Pearl Harbor is to be reminded of how much uncertainty and suffering lay ahead for Americans on Dec. 7, 1941. We owe a debt to those who faced those terrors — and defeated them.