If we do the math(s), at some point the murders by right wingers could become so frequent and bloody that they stop being just a series of actions by individuals and qualify as a war.
Bush declared war on terror in 2001 after 19 people staged 4 simultaneous attacks, killing 2996 and injuring about 25,000. At the time, al Qaeda considered that they'd been at war with the US since 1992.
What would it take for the President or the American public or Fox News to acknowledge that a civil war has started? Some of the right wing extremists think it started long ago.