The Democrats, as they were in the major Civil War, are on the side of paternalism, like slavery and the South. The Republicans are on the side of pro-commerce, open markets and government restraint.
As in the major Civil War both sides took a moral position. However, the provocative South attacked the moral fabric of the North by pushing the Dred Scott decision that forced Northerners to return slaves to the South. An odious proposition. Similarly the South pushed the great compromise in which half of new states were to be slave.
The current Democratic incitement of moral indignation by the Republicans is threefold. First the press has become more aggressive and partisan in the past decade. The media has gone so far as to call Republicans liars in every newspaper and nearly every TV newscast. This is a moral challenge because the Democrats are the worst liars as exemplified by the outrageous Harry Reid, as the Majority leader of the Senate who fabricated a 10 year tax holiday for the Republican presidential candidate.
Second, the Democrats have screamed racism 10 times a day when no circumstances supported it. Again a moral issue in which Republicans are innocent and the Democrats are historically guilty (think race warriors like Al Sharpton).
Third, the Democratic president has aggressively attacked the idea that America is a fair society with great opportunity for everyone to succeed on their own merits. This attack is a moral attack on fundamental Republican views of America.
The civil war today is fully underway and the moral attack from the Democrats will assure that this civil war will last many decades.