You miss the point. There are white muslims. There are white muslim terrorists. Trying to say only Arabs are terrorists allows terrorist groups to use their white foot soldiers to accomplish their goals.
Your simplistic thinking leaves quite the security hole.
http://news.scotsman.com/latestnews/AlQaeda39s-white-army-of-terror.3667425.jp
http://www.balkanpeace.org/index.php?index=article&articleid=14021
We were talking about 9/11. The hijackers were all mid-eastern muslims and they looked like it. End of story.