Final answer:
New military facilities, naval and air production, ammunition plants, and petroleum production were necessary for national security and to support military operations during times of war. These industries provided the resources, equipment, and supplies needed for the military to defend the country and carry out missions effectively.
Step-by-step explanation:
During times of war, the following industries were necessary for national security and to support military operations: new military facilities, naval and air production, ammunition plants, and petroleum production. These industries provided the resources, equipment, and supplies needed for the military to defend the country and carry out missions effectively. For example, naval and air production was crucial for building ships, aircraft carriers, tanks, and armed vessels, while petroleum production was needed to fuel engines and generate electricity.
Additionally, these industries contributed to the overall economy by creating jobs and stimulating other sectors. The construction and automobile industries, as well as industries such as steel, oil refining, rubber, and lumber, employed thousands of workers. The production of military equipment also required standardized parts and fabrication processes, which led to advancements in manufacturing techniques.
Furthermore, good transportation was essential for moving raw materials, finished goods, and troops. Efficient transportation networks facilitated the flow of resources and ensured access to markets, both domestically and internationally.