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Operation Rubber: basically the US was afraid of Brazilian sympathies to the Axis and wanted access to Brazilian ports as they were the closest in the Americas to North Africa. So after Pearl Harbor, the military made plans to invade Brazil but held off after Vargas agreed to allow the US to use Brazil's airfields.

What if the US decides to go through with Plan Rubber, how would the invasion go, what would be the larger effect on the War?
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