The problem is that Japan will still attack the US at Guam, Wake Island, and the Philippines......unless they want to give up the pacific war entirely? So Roosevelt just needs to reframe why US is fighting and IJA will anyway create plenty of reasons after the fall of the garrisons with its treatment of POWs?For the political establishment, but what about society at large? Roosevelt rejected all suggestions of pre emptive attack.
For the US to fight WWII, the country had to be united. If it entered divided as it had WWI, measures like rationing would be unavailable.
If 30% of able men either redused to register for the draft, report when called or deserted begore finishing boot camp ( the WWI figure), its hard to see America fighting anything like the war she fought