There are several elements of the Great American Civil War that are present today and worth examining.
We have in both cases an open political division of the country over the moral role of America in the world. The two main parties (the same as in the Great Civil War), the Republican Party with its radical Tea Party wing, believes that the purpose of America has been denied and rejected by the Democrats in power. The Democrats believe they have the mantle of righteousness on their side.
The sides are slightly changed over 150 years. In the Great Civil War the party that came to power was the Republicans and it was the Republican party that began making major changes toward the Republican moral position (anti-slavery)... today it is the Democrats who are making changes to dismantle the American moral role in the world.
In the Great Civil War the underlying issue was slavery and the public issue was expansion of slavery to new states.
Today, as before, the underlying issue is the moral leadership of the United States in the world. Today, the Republicans again believe that America must be a moral leader. It is no longer an issue of domestic slavery, it is now an issue of defending the American vision of Democracy, religious freedom and Commerce in the world.
As with the Great Civil War the Democrats use euphemism (the ‘peculiar institution’) to describe their anti-moral position. Today, the Democrat euphemism for the moral war against Islamic militants is ‘overseas contingency operations’.
The emerging issues then as now were overlays to the underlying moral leadership role of the United States. The Republicans want the Mexican border closed so anti-Democracy aliens can’t sneak into the country, want a strong military presence in Iraq and Afghanistan, want North Korea and Iran to be disarmed of nuclear weapons, want the only democracy in the middle-east (Israel) to be supported fully, want the domestic economy to be a fiscally balanced as possible for a global leader, without new draining government entitlements, and with little or no effort by the government to run the economy with stimulus or direct control of corporations. The Republicans are proud of the concept of American exceptionalism. The Democrats are on the other side of each issue and believe America has often been wrong globally, created antagonism unnecessarliy and needs to emulate a more modest European social and international model.
The country, today, even has a state by state division, Red and Blue, but the state divisions cover the more significant local divisions which are cities versus suburbs and exurbs.
No open warfare can grow from the current Civil War but the parallels are disturbing.