The other day news analyst Juan Williams was fired for stating that when he sits next to someone on an airplane wearing full Muslim garb that he becomes afraid. He commented that if someone chooses to identify themselves as a Muslim by their clothing, that they are more likely to commit an act of terrorism. There were people who found his remarks to be hateful and anti-religious; others applauded him. Whichever side of the argument you are on, I would like you to take a good look at some of the more notorious terrorists or terrorist supports that have been in the news lately and tell us if their clothing frightens you. These are examples of the style of clothing worn by terrorists from all over.
Suits and ties, baseball shirts and hats, jeans and sweatshirts, button-down shirts, camouflage gear...these are the items the terrorists wore in their every day life. In fact, every single one of the 9/11 terrorists wore western garb when they boarded the airplanes that day, and they wore Muslim garb in their passport photos.
If you are looking to clothing as an indication of terroristic propensities, I think you should remember that "clothes don't make the man". Or the terrorist, apparently.