Final answer:
Andrew Carnegie is one of the first defense contractors in U.S. history, known for his significant contributions to the domestic steel industry, which were vital to military infrastructure.
Step-by-step explanation:
One of the first defense contractors in U.S. history is Andrew Carnegie, who was instrumental in creating the domestic steel industry crucial for military infrastructure. Carnegie's steel production techniques, bolstered by controlling the entire production process, directly supported railroad development and the expansion of the U.S. Navy. Through his company, Carnegie financed and invested in technologies and resources that allowed him to produce steel at competitive prices, eventually leading him to create U.S. Steel Corporation after selling his holdings to J.P. Morgan. One of the first defense contractors in U.S. history was Andrew Carnegie. Carnegie rose from humble origins to become the leading steel producer in the world. He sought to control every aspect of steel production and lower costs by direct ownership of mines, foundries, and railroads.