Prejudice, whether it takes the form of racism, bigotry, sexism, homophobia etc, is born of fear, insecurity, feelings of powerlessness and inadequacy. To act out of prejudice, (as the terrorists did in the 911 attacks), is to give up personal responsibility and self control, and allow yourself to be consumed by your fears, insecurity and inadequacy, thus completing the cycle of hate and violence, and becoming truely powerless.
The truely strong and powerful, do not need to seek to destroy , or demean others, to gain that strength. Their strength, courage and power comes from within.