Red Crescent to be Memorial for Terrorist Victims

Someone sent me this story about the Memorial for Flight 93 and I looked at the picture and my jaw dropped.

I understand that the red crescent is not in and of itself a violent symbol...but considering that the hijackers were killing in the name of Islam, this seems a bit insensitive.

The wierd thing is I couldn't find any mention of controversy in the article.

Real Clear Politics is not as silent on the subject.