How did the growth of the United States through purchase, war, and treaty affect EVERYONE living within its borders?

It affected everyone because they all need things. It wasn't helpful that the wars began expanding, but we all do great with these things.

Explanation:

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.

thomas jefferson is the answer