Can someone simplify this paragraph?
On the morning of December 7, 1941 military forces of the Empire of Japan attacked the United States Naval Fleet and ground bases at Pearl Harbor in Hawaii. On December 8, 1941, one day after the “Day of Infamy,” the United States declared war against the Empire of Japan and on December 11, 1941 Japan’s ally, Germany, declared war on the United States. Sixteen million Americans, mostly young working age men, would serve in the military during WWII, out of an overall United States population of 113 million. While an unprecedented number of young men would serve in World War II, the country would drastically increase its war production on the Home Front, serving not only the needs of the armed forces of the United States but her allies as well - what President Franklin Roosevelt called “The Arsenal of Democracy.” The combination of so many serving in the military, during a period of necessary and drastic increases in production, led to unprecedented social changes on the American Home Front.