How did war and diplomacy change the United States and people's lives in the
early 1800s?

It greatly affect the life of American people.

Explanation:

Due to war with the powerful military of Britain, the United States earn respect in the world and sense of nationalism was also produce among the citizens of United States. The first war which was fought in 1812 by United States against Britain and its alliances. The main cause of this war was the economic sanctions that was taken by the Britain and French against the United States. This war won by Britain against United States by defending its territories in america.

answer; validity;