How did the Emancipation Proclamation cause a change in the goal of the war?

It became a morally driven war from the North towards the south, post emancipation the freed slaves took arms and fought for the north. This enhanced the Norths manpower whilst depleting the Souths slave-based workforce/economy.

The Emancipation Proclamation extended the scope and purpose of the US Civil War beyond preservation of the Union to encompass wider moral, social and ethical considerations involving abolition of slavery.

The emancipation proclaimation shifted the primary goal of the war from maintaining the Union to abolition of slavery throughout the Union.

The Emancipation Proclamation altered the goals of the American Civil War. Initially, the Civil War had been a response to the secession, breaking away of the Confederate States, and was an attempt to bring about reunification. However, as the war developed so did Lincoln's aims. The war that was started over the debate over slavery was changed when Lincoln Emancipated the slaves. Thus their was a new moral and military drive to the war. Now the United States had a much wider support base and men to fight as soldiers after the Emancipation. This change meant one term of victory would be the ratifying of the Emancipation and official abolishment of slavery.