Because the war was wide spread and there was a need to supply millions of soldiers and sailors with the materials and machines they needed to fight. This was a true world war with fighting going on in much of the world .
As an example: the war in Europe might have lasted a year or two longer if it had not been for the ability of American to quickly produce all of the landing craft needed for the D-Day invasion.
He wrote his works based on ideologies on what he believes the economy should be
An innovative way was an improvised vaccination.
This consisted of smearing open cuts of healthy people with substances taken from wounds of sick people (for example sick from smallpox) in the hope that they will undergo a mild version of the disease and when the disease catches them, not die.
The risk was that they could get seriously ill, but the advantage was that on average, they had better survival chances than without this "vaccine"
