In 1941 a B-25 Mitchell bomber contained 107,156 rivets, each one inserted by hand. Often a woman’s hand.

That year, there were as many people on the left such as Lowell Thomas and Al Smith, who were part of the isolationist America First Committee as there were people on the right, such as Charles Lindbergh and Herbert Hoover.

The U.S.O. was created in 1941, as was the comic book character, “Captain America.” The first time an organ was played at a baseball game was in Chicago in 1941 and the first television commercial aired was in 1941 to tout Bulova Watches.

In 1941, the United States of America went to war with the Axis Powers including Japan, Germany and Italy, changing America radically and forever.

Just three days before the December 7th attack President Franklin Roosevelt received a long memorandum marked “Confidential” from the Office of Naval Intelligence, reviewing in detail all the subversive activities going on in America, including those emanating from the Japanese Embassy in Washington. “The focal point of the Japanese Espionage effort is the determination of the total strength of the United States. In anticipation of possible open conflict with this country, Japan is vigorously utilizing every available agency to secure military, naval and commercial information, paying particular attention to the West Coast, the Panama Canal and the Territory of Hawaii.”

The response of the U.S. military, government and citizenry to the events of December 7 was quick and decisive, even if it was also often bumbling and haphazard. “Everyone, I suppose, will be jotting down in a little black book somewhere the memories of Sunday, December 7—where they were, what they were doing, what they thought when they first heard of the war. Let me tell you—you don’t have to make a note of those things. You’ll remember them.” So wrote famed sports columnist Bill Henry in his “By the Way” column in the Los Angeles Times on December 9. This was true enough, but the entire thirty-one days of December 1941 were memorable, messy, historic, poignant, confusing, inspiring, depressing, and enduring.

After December 7, 1941, the policies towards the Japanese, Germans and Italians living in America were harsh and comprehensive but because the government believed the Germans and the Japanese had incredible spy and sabotage networks operating in the United States and the Hawaiian Territory, the reaction by the government at the time, they felt, was justified.

At the end of December 1941, Americans still weren’t calling it “World War II” or the “Second World War,” though there were hints of the standard appellations to come. Even three weeks after America’s entry into the global crisis, Americans were still calling it the “national emergency” or “the war.” I didn’t learn many of these and thousands of other things just from researching books during the development stages of December, 1941; I learned many of these facts from the newspapers, magazines and other publications of the era as well.

Washington Post publisher Phil Graham once said, newspapers were “the first rough draft of history.” So much of the sourcing for this book comes from hundreds of newspapers and thousands upon thousands of newspaper and magazine articles around the country and wire service bulletins and radio dispatches and short-wave intercepts sifted through to build the following account. But private diaries, personal papers, and confidential and classified material were also heavily relied upon for this story.

There have been days such as July 4, 1776, October 19, 1781, September 17, 1787, and April 15, 1861, that rank with December 7, but one is hard-pressed to think of another month as startling, compelling, interesting, critical and inspiring as December 1941.

Never before or since has America been so unified. There were virtually no Americans against their country getting into World War II after the unprovoked attack by the Japanese at Pearl Harbor. One of the few was Congresswoman Jeannette Rankin, Republican of Montana. She voted against declaring war on Japan and would only vote “present” when FDR asked the Congress for a declaration of war against Germany and Italy—after they had declared war on America. Someday someone will write a book about Ms. Rankin, exploring her reasons for not voting for war. They were principled, nuanced, and commendable. She was mistaken but she wasn’t wrong.

The goal here is to make the reader feel as if they are experiencing the day to day events as they unfolded. Some historians don’t like to go into the arduous tasks of going through thousand of newspapers preferring instead to rely on those bits and pieces of news reporting they may glean from other books. I did and consequently the reader will find stories and information from the month of December 1941 they have never heard before.

President Roosevelt, Prime Minister Winston Churchill, General George C. Marshall, Admiral Chester Nimitz, General Douglas MacArthur, and many others in both the Allied and the Axis Powers are here. Prominent Americans including political leaders, actors and athletes are here. Yet they are all merely supporting cast members in this drama.

The central and most important actor in December, 1941 is the United States of America.

Craig Shirley, president of Shirley & Banister Public Affairs, is the author of "December 1941: 31 Days That Changed America and Saved the World." Andrew Shirley was the Chief Researcher for December 1941: 31 Days that Changed America and Saved the World.