Woman forced from Fed building for lesbian shirt

I sometimes wonder what makes people think that they can commit senseless acts of stupidity and get away with it? If you work for someone else, what is it that drives you to do something that you know your company is not going to back you on? Is homophobia really such a driving force that you will do something you know will probably get you reprimanded, if not fired? I think back to the heyday of the Klan, and lynching; those people knew that for the most part, society would allow them to get away with the things they did, through ignoring the situation, saying it was the victim's fault because of some small action, or just getting rid of the situation through intimidation and murder. In this situation though, what made this security guard think that he could get away with this? He cites a policy which he evidently had not read; if he had, he would have known that it did not mention clothing, and he would not have made even more of a fool of himself than he already had. It is amazing to me that someone's bigotry/homophobia could run so deep that a word on a shirt could make him react that way. I have seen people react to some strange things in some strange ways, but this one takes the cake. I wonder what that guard would do if I went in with a rainbow pussy t-shirt on....