How are the details presented about American production before and during the country’s involvement World War II important in supporting the central idea of the passage?

America's isolation from war ended on December 7, 1941, when Japan staged a surprise attack on American military installations in the Pacific. The most devastating strike came at Pearl Harbor, the Hawaiian naval base where much of the US Pacific Fleet was moored. In a two-hour attack, Japanese warplanes sank or damaged 18 warships and destroyed 164 aircraft. Over 2,400 servicemen and civilians lost their lives. Though stunned by the events of December 7, Americans were also resolute. On December 8, President Roosevelt asked Congress to declare war against Japan. The declaration passed with just one dissenting vote. Three days later, Germany and Italy, allied with Japan, declared war on the United States. America was now drawn into a global war. It had allies in this fight--most importantly Great Britain and the Soviet Union. But the job the nation faced in December 1941 was formidable.

the anwser is a) to prevent military conflict