The question of slavery is indeed one of great significance and receives much attention when it comes to discussing why the soldiers fought the War. There were, of course, thousands who professed to be fighting solely for the abolition of this sinister institution. But in the letters McPherson read of Northern recruits (a sample of 647), a states that "few Union volunteers mentioned the slavery issue when they enlisted." However, he details in Chapter Nine that that most soldiers professed the preservation of the Union to be the chief purpose of the war, but with that came the need to strike down slavery as well. The idea that the end of slavery was inextricably bound to the cause of Union was one that three in ten soldiers whose letters he examined expressed. He goes on to indicate that more would be converted to this school of thought as the War progressed (for reasons too numerous to list in this article, but would make well in a later discussion).
McPherson does point out that the attitudes of many of the soldiers were "more pragmatic than altruistic." Within this notion resides the fact that because slavery was depended upon as the chief economic sustainer in the South, the freeing of as many slaves as possible would expedite the South's downfall. "I don't care a damn for the darkies," wrote an Illinois lieutenant, but "I couldn't help to send a runaway nigger back. I'm blamed if I could. I honestly believe that this army [in Tennessee] has taken 500 niggers away from them."
Not all in the North felt a sense of pragmatism or altruism when it came to the Negro. About 2/5 of the soldiers came from Democratic backgrounds and another 1/10 hailed from the border states that still clung to the institution of slavery. McPherson states in regards to this large minority of soldiers that the cause of Union united the Federal army while the cause of emancipation divided it. Following the Emancipation Proclamation, a good number of soldiers expressed a feeling of betrayal by Lincoln, saying they would fight and die for the Union, but not for the freedom of the slave.
The author cites an interesting poll taken in the 15th Iowa regiment in March 1863 where half the men favored emancipation while a quarter opposed it, the other quarter remaining silent. McPherson then divides the respondents in the poll into socio-economic backgrounds. He reveals that pro-emancipation sentiment was overwhelmingly coming from an over-represented group: officers and men from professional and white-collar backgrounds. Forty-two percent of the officers supported emancipation, whereas 33 percent of the enlisted men agreed. Further, among those with "prewar professional and white-collar occupations, those who favored emancipation outnumbered opponents by four to one."
