It had drafted men ages 18 to 45 years old. This resulted in a total of 2 million
Americans volunteering for the War. It
increased the size of the U.S. army.
This was due to the patriot fervor that griped the nation to fight
during the First World War.
There was more than one technology that was developed at the time, but one technolgoy that surely made a strong impact and also enabled Europe becoming the dominant military force was the invention and perfection of military tactics together with muskets and cannons. This made them practically unstopable against any native population around the world.
Northwest ordinance is the answer