It is not hard to believe since many Americans were totally outraged by the devastation of the attack on Pearl Harbor, which catapulted us into WWII.
Most Americans were outraged by the 9/11 attacks as well. Had the US gone to a total war footing then, I don't believe the population would have been so accepting of the sacrifices required. The vast majority has never known a time of severe deprivation and hardship, unlike those coming out of the Depression. The gas crunches of the 70s and the recent tough economy pale in comparison.
How long would people tolerate the lack of luxuries that even the "poor" have enjoyed for the last 20+ years. 100% of industry dedicated to the war effort, no computers or cell phones (no guns and ammo for the likes of us), no buying a new car or house, watering down milk to feed your children, meats, vegetables, flour, sugar, butter limited to a few pounds a month, gasoline and coal severely limited- when its gone, there is NO more until next month when your ration books come, regardless of how much cash you have.
As Saxman said, nothing like it had happened before or since; fortunately, the Greatest Generation was well prepared for such hardship by a decade of economic depression.