Final answer:
Union troops adapted to Confederate strategies by holding strong defensive positions and countering flanking maneuvers. The Battle of Gettysburg and the Battle of Antietam illustrate these tactics and the broader operational challenges of the Union forces.
Step-by-step explanation:
During battles, Union troops had to adjust their troop movements to respond to the strategies employed by the Confederates. A notable example of such adjustment can be seen in the Battle of Gettysburg, where the Union held advantageous defensive positions along crests of hills and could counter Confederate attacks from there. When the opponent attempted to flank, Union forces held their ground, and if the flanking maneuvers did not succeed, the attacking force typically shifted to a direct assault. This military strategy is reflective of the larger challenges the Union faced, such as having to conquer and pacify large areas, unlike the Confederacy, which focused on defending. The Battle of Antietam also showcased the importance of decisive action; Union General McClellan's hesitance allowed Confederate General Lee to withdraw and avoid a conclusive defeat.