Some historians have claimed that the Mexican War was the first battle of the Civil War. Do you agree? Why or why not?
It can be considered the first battle of the Civil War because victory in the Mexican War brought new territories which would eventually become states under US control. However, the government at this time had not devised a permanent and reliable way to add states without inflaming the slavery debate. As such, by bring more states into the Union and adding pressure to an already weak system, the Mexican War can be seen as a precursor war (or first battle) to the Civil War.