Final answer:
At the start of the Civil War, both the Union and the Confederacy believed they could win quickly, but the First Battle of Bull Run showed the war would be long and harsh. The Union had the advantage in resources and infrastructure, while the South aimed for a quick victory to maintain its independence and way of life.
Step-by-step explanation:
At the onset of the Civil War, there seemed to be no clear winner. While the Union had greater resources, they underestimated the South's anger, and the Confederates underestimated the North's determination. The first major battle at First Manassas (also known as the First Battle of Bull Run) made it evident to both sides that the conflict would be lengthy and brutal. Initially, both the Union and the Confederacy believed the war would end quickly, but as the battle progressed, the grim realization of a long-term war set in.
Reactions and Strategies
Northern citizens initially had high enthusiasm for the war, expecting a swift victory. However, the realization that the war would be a drawn-out effort likely caused various reactions ranging from steadfast resolve to perseverance to dismay among the populace. The Union strategies relied on its larger manpower, industrial capabilities, and extensive railroad network, which allowed for better mobilization and supply movements. Conversely, the Confederacy, fighting defensively, hoped to quickly bring the conflict to an end to ensure its independence and maintain its way of life, central to which was the institution of slavery.