By Marc A. Levin and Khalil A. Cumberbatch

The U.S. stands at risk of future instability, and perhaps even the grim prospect of states seceding from the Union, a recent Canadian intelligence report suggested. Even though a new poll finds that 21 percent of Americans think we would be better off splitting into separate red and blue nations, this prospect is unthinkable and unlikely, not to mention unlawful.

But as more Americans express an openness to engaging in political violence and arm themselves for a variety of reasons, we must stand strongly united against a rising tide of separatism, domestic terrorism, and vigilantism — whether it comes at us from the right or the left.