we look like idiots
It's not only a question of looks, stupid nonsense is idiotic, yes.
"I am afraid that you are confused. I am a foreign sovereign with respect to you, and even if I wanted to be a "sovereign citizen" neither I nor anyone else could answer to that, because "sovereign citizen" is an oxymoron. No such thing exists by definition."
So you deny that you're one? If you're not one, why would you be considered to be one? This means that the "Americans" above is not about "Americans" but about those who deny its government and laws? The same reason some call themselves "patriots", because it's also an oxymoron for their anti-US position?
So, even when you are angry because some confused and ignorant British Territorial or Municipal citizen misaddresses you, understand that you don't stand under their government
So that's your straw man for the government and it explains all of the above. You've exposed yourself as espousing anti-government conspiracy theories and pseudolegal arguments, a common feature of the "sovereign citizen movement" and its offshoots.