What we say doesn't matter. What the Red Cross says doesn't matter. The Geneva Convention protects certain symbols. That's the end of the debate. The red cross/crescent is owned by the Red Cross and any use by anyone else is completely subject to their permission.
This system was setup for a good reason. Those of us whose lives may one day be protected by that symbol (wounded soldiers) need it to remain above reproach. Every soldier may one day be bleeding on a cot in a field hospital, that symbol on the tent his only protection from instant death. The use of the red cross/crescent/crystal/star is not something that should be up for constitutional debate.