Which of these events first loud many more settlers to move west in the 1800s

although world war i began in 1914, the united states did not join the war until 1917. the additional firepower, resources, and soldiers of the u.s. to tip the balance of the war in favor of the allies. remaining neutral. when war broke out in 1914, the united states had a policy of neutrality.

which statement explains one of the reasons world war 1 was so much more destructive than earlier conflicts