The polls had changed by Sept. of 1941. Actually the isolationist position had peaked in about 1937, but after the conspicuous failure of the "Munich Agreement", and silliness of appeasement appeared, it began to wane. Then at least one nation they had held up as an example of the success of their stance; "neutral non-involvement" (Belgium) was over-run by an even more aggressive Germany in spite of a promise by Hitler not to do so. Then they pinned their hopes on the defensive stance of a strong (military) as in France, it too fell to Nazi aggression. So the ambivalence of the public mood in the late thirties clear into 1941, became more and more evident as the Nazis overran western Europe and Scandinavia; signed "non-aggression pacts" with Stalin’s Soviet, drove the BEF off the continent, and then attacked Britain by air. In one of the last pre-war polls during the last weeks preceding Pearl Harbor, Gallup's interviews concluded (less than a week before the Japanese attack) that while about one-quarter thought war was avoidable and could be forestalled if not eliminated, slightly more than one-half of Americans expected that "the United States will go to war against Japan sometime in the near future." Earlier a similar percentage had expressed a "willingness to risk war with Nazi Germany in favor of Great Britain." (emphasis mine) This was shortly after that lying snake Hitler had once again ignored a treaty and or pact and invaded the USSR in mid-41! In short order Hitler had made and broken "non-aggression pacts" with Poland and the USSR, promised to observe Belgian neutrality, and over-run it, invaded both Denmark and Norway, and defeated France. In short, from a historical point of view using both hindsight and then existing public opinion, it appears probable that (even if the Japanese had not taken the initiative), the American public would soon have endorsed the U.S. entering the war anyway. Thus, in the period directly preceding Pearl Harbor, Americans were shifting gradually, but more and more rapidly away from their prior mood of introversion/isolation to the mood of extroversion/intervention. As an amusing aside, those polled in the land-locked mid west and mountain states were the staunchest "isolationists". Likely feeling safe so far from the ocean shores. Those polled on the coast-lines had a more realistic and pragmatic approach, in that they favored building up our defensive forces (conscription and weapons purchase), but only for self-defense. The smaller group of total pacifist isolationists were against any war at any cost, while the greater share were for self-defense, and retaliation if attacked, but not declaring war unilaterally. These polls were taken of voting age male and females in the US prior to the Pearl Harbor attack. Gallup poll #248, Question 3 (mid-Sept 1941), 55% of Americans believed that the country was already involved in the war. As shown in Question 5K and 5T of the same poll, a little over 1/2 of all Americans believed FDR was doing the right thing with his actions (that 55%), while about another 20% believed he hadn't gone far enough. A near complete reversal of the numbers from early 1941 when only about 17% favored going to war! (there are your early early '41 numbers ANZAC) Furthermore, in Question 6 of Poll #248, 60% of Americans approved of the decision to fire on German submarines. Finally, a great majority of Americans answered in Questions 11K and 11T that American democracy and German fascism could not co-exist. Now, while in that same poll the vast majority answered they did not want to declare or go to war unilateraly at the time, they approved of FDR's actions (Gallup Poll #248, Question 13 revealed that 2/3 of Americans support FDR's policies in general as well as his foreign policy specifically by Sept.).