(a) it must be a foreign entity;
(b) that foreign entity must be a (recognized) state actor; and
(c) there must be a formal declaration of war.
I guess my question to them is, have you read the passage? Can you point out where it specifies a, b and/or c? Of course, for anyone with a clue, it's a ridiculous construct on its very face. Using their defined characteristics, for example:
1. A US citizen aiding & abetting in Pearl (eg sabotage of defensive capability) would not be guilty of treason since a state of war technically didn't exist before the attack.
2. A mutiny by the armed services in an attempt to mount a military coup would not be treason since it wasn't (i) a foreign power; and (ii) there wasn't a declared state of war.
I could go on, but I assume people will quickly grasp the point. The bottom line is, under no possible scenario do organized, domestic (non foreign, non recognized state) conspirators get a pass for attempting to overthrow (state of war doesn't exist, nor is it formally declared) the legally constructed government of the USA.
A favorite phrase I see around the interwebs these days is the founders - you know, the guys who wrote the document - would have already been stacking bodies by now.
They definitely tried to overthrow a legally-elected President.