"Ms Bhutto said before leaving that she was undeterred [by threats of attacks]: "I do not believe that any true Muslim will make an attack on me because Islam forbids attacks on women and Muslims know that if they attack a woman they will burn in hell." (link)
It's very hard for me to fathom what possessed her to say this. Obviously, she knew full well that such bravado wasn't going to deter a single would-be bomber.
With more than 100 people dead after someone did subsequently attempt to assassinate her, it now seems incredibly irresponsible. It's a taunt, or a bluff -- but bluffs are only good if your enemies can't call them.
(There are some biting comments from Karachi residents about Bhutto here and here)