ISIS aren’t the only radicals in the world.
He might have converted to anti-Trump marxism.
I have facebook friends of friends who have advocated violence against conservatives, who they call “nazi’s” for not being in lockstep with the hard left.
Alex Jones said his source told him there was Antifa literature in the room / sniper nest.
I also have seen CNN etc. and the DNC leadership refer to Trump and his supporters as “white supremacists.” Certainly would explain him targeting country music fans thinking they are Trump voters.