The Battle of Antietam affected military tactics moving forward by prompting the introduction of new strategies.

The significant casualty rates and harsh realities of warfare highlighted the shortcomings of conventional tactics when confronted with modern weaponry like rifled muskets and artillery. Military leaders started to see the necessity for more creative strategies, which included enhanced coordination between artillery and infantry, more effective use of cover, and strategic movement. These adaptations set the stage for the development of new tactics in future battles, as both sides adjusted to the changing landscape of industrial warfare.