By choosing to adopt isolationism, the USA caused many problems for itself and the world.This lead to a limited amount of foreign resources and also export income.One of the most influencing effects of the isolationism was the lack of American support in the League of Nations By staying out of the peace keeping group, the USA left the other democracy with no power or leverage over the Aggressors of WWII. The non-intervention policy of the USA left its allies, the British and French, with no support against the superior Axis Powers. This effectively caused the fall of Paris in 1940.
