Because when the natural rubber supply from Southeast Asia was cut off at the beginning of World War II, the United States and its allies faced the loss of a strategic material. <span> So the companies, in collaboration with a network of researchers in government, academic, and industrial laboratories, developed and manufactured in record time enough synthetic rubber to meet the needs of the U.S. and its allies during World War II.</span>
One of the major impacts of American intervention during World war 1 was an increase in American industrial output.
<h3>American Intervention during WW1</h3>
The United States had earlier remained neutral at the start of the war.
American support towards the war was mainly from individuals and it was in form of relief efforts such as voluntary ambulance drivers or nurses, or even as pilots and soldiers.
This intervention from America saw a great industrial output in order to meet the demand of their allies such as Great Britain and France.
Americans had been sympathetic to the allies and saw the German empire as the main oppressors in the war.
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They conflicted with the fifteenth amendment to the united states constitution which prohibits the federal and state governemtns from denying citizens the right to vote based on that citizens race color or previous condition of servitude.