The crescent is still there. Tancredo is a fool if he thinks we're going to fall for this nonsense.
Reality check!! Tancredo had nothing to do with the Flight 93 Memorial design. He was appalled when he saw the original crescent and tried to get the architect to change it. As you can see by the Islamofacist shrine link, the architect pulled a fast one in his "redesign".
Direct your comments to the architect and the National Park Service. They are the appropriate contacts.