I think a civil war is likely, but not necessarily an open war fought with guns (though there will be plenty of those), rather a war fought with denial of aid to those in desperate need after natural disasters and other catastrophes.
In otherwords, civil war is coming but it will look more like a series of endless Hurricane Katrinas except this time the president will actually laugh at the people dying as part of his public speeches.
Denial of critical aid is a reliable rationalization for martial law to a racist audience, you just need to let things truly start to break down, point and say "they are out of control!!!" and you are good to do whatever they hell you want in the minds of centrists who believe really hard that they aren't racist.
Exhibit A: How the U.S. and Europe treated and still to this very moment treat Haiti