Don't be. Although it does look like a kind of civil-cold-war is the order of the day, I doubt it could come to open violence in the streets. Never the less, if it did, we wouldn't lose. Think about it, how many libs own guns as a percentage compared to republicans. They may control the cities but exactly how would they get food? 
For that matter if it did become a real civil war how would the libs organize? They usually don't trust the military culture, I mean can you really see your average lib trying to hold, say, New York from a Republican militia? Assuming the military and the official government, at lest stays neutral the libs don't have a chance strategically. Worst case scenario is the governments sides with the libs and the military goes along with it, and that is totality unlikely considering that any violence will likely be started by the libs anyhow.