From an essay on WWII campaigns, (
http://histclo.hispeed.com/essay/war/ww2/cou/us/ww2us-iso.html ), One
of the driving forces of isolationism in the 1930's was a combination
of perceived corruption and profiteering during the 1920's as it
related to war and foreign policy, when combined with the depression
and bad economic times of the 30's many felt it more important to deal
with domestic issues rather than foreign ones. Some, such as Charles
Lindbergh, believed we could not win a war against the German army.
President Roosevelt on the other hand saw the dangers of the German
army, and with resistance got the support needed to fight back.
From the same site, it states that America historically was
isolationist unlike today, and that the reason we entered WW1 was
primarily due to the threat to our shipping via the german submarine
In addition to not meddling with the affairs of other countries,
Americans at the time were generally not inclined to support any
government involvement. At the begginning of the depression, President
Hoover was not willing to commit government resources to stabilizing
the economy. This kind of attitude changed however when President
Roosevelt was elected in 1932 and brought about "the new deal". This
was the catalyst for a major change of attitude of americans, who were
now willing to allow government a more active role in managing the
economy, and paved the way to more acceptance in its increasing role
of world politics.
An excerpt of the book Women of the Far Right: The Mother's Movement
and World War II ( http://www.h-net.org/reviews/showrev.cgi?path=2802894487938
) mentions that one of the forces for isolationism was the
"ultraconservative women's groups which organized in protest of U.S.
involvement in the Second World War."
From the previous article, there was great anti-british mentality in
the united states fostered by the irish and italians, which was
further promoted by previous tensions with britan over the
revolutionary war, threats of war over oregon territory, and british
involvement with the south during the civil war. These combined to
have a great effect on the general public being against involvement in
the second world war.
The biggest push for anti-isolationism documented seems to come from
President Roosevelt who had to fight a great deal of public opinion
and put his own spin on things to even generate the kind of military
readiness to fight the war.
Clearly, the greatest catalyst for our involvement and disregarding
our isolationist attitudes was the attack on perl harbor, which
gathered a great deal of support for the united states to enter wwII.
I hope this provided the kind of information you need.
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