What they are really saying in this passage is that the country is one supreme court justice away from civil war.
I think a "Constitutional Crisis" is more likely than "Civil War".
Look at Baltimore, Chicago, NY and other big US cities this past Summer, showing how cops react when people armed with phone cameras threaten their livelihoods and pensions.
The US is a nation of (top end of the estimates) nearly 400 million guns in the hands of over 100 million gun owners. How are they going to react to the knowledge of what will threaten their lives if they try to enforce some sort of gun ban?
This article lays it out pretty clearly. Pay attention to Step #5.