How does Lincoln speech address the north’s interest

On March 4, 1865, in his second inaugural address, President Abraham Lincoln spoke of mutual forgiveness, North and South, asserting that the true mettle of a nation lies in its capacity for charity. Lincoln's second inaugural address previewed his plans for healing a once-divided nation. He argued that all Americans—North and South—shared culpability for the unimaginable horrors the nation had endured. This war of unexpected duration and ferocity, he posited, may have been God’s judgment on all of America for the evil of slavery.

Every statement this is because of the same law