Re the WWII preparedness thing - FDR had been trying to engage in the war, as he thought it was both inevitable and unavoidable, much of the congress and the country thought that it was "their" problem, over in Europe, or Asia, or wherever. I'm pretty sure that the American military was aware that it was a real war and had plans.
The country at large had managed to ignore the war. Pearl Harbor was a complete surprise to my father's family. They really didn't believe that it was a real war that could possibly affect their lives. December 7 changed that perception, my dad was in line down at the courthouse on December 8.
My mother's parents were living in Buenos Aires, Mother was at nursing school in St. Louis, and she'd been unable to go home to her parents for a couple of years because none of them were willing to risk meeting a U-boat at sea. They were less surprised by the war, per se, but still shocked by the Pearl Harbor attack.
I'm not surprised that the military was expecting involvement in the war - they have a different perspective than civilians do. As long as the military is subject to civilian control, as ours is, all they can do is prepare as well as they can within the available funding, and hope for the best. Preparedness is the military's obligation.
It was not so much a matter of delaying engagement until we were ready, as not believing we'd need to engage at all. There was a major disconnect between those who felt that America was isolated by those nice wide oceans and those who felt part of the world at large.
