Great point. Visit any US neo-Nazi website and you’ll see language that one could argue is “threatening to a specific group”. But unless it’s “hey, everyone gather at 5 pm on Main St so we can start shooting people”, it’s still protected language.
That's actually a point that I don't think has been decided yet, specifically "imminent". It's been ruled that "at some unspecified point in the future" doesn't count, but I can't find a case (with an admittedly short search) about where the exact boundaries are.
I don't know what the exact legal definition of imminent is, but the layman's definition involves the thing happening soon.
It may well depend on how close to 5 it is (but what timezone?).
The same sentence with the words "right now" would almost certainly meet the test though (assuming the action was actually likely to occur).
