They warn of Islams dangers to a free society. They document the testimonies of Muslims who have left Islam, and had their lives threatened. According to them, the penalty for leaving Islam (apostasy) is death. Both Sina and Warraq are EX-Muslim Arabs, so you cannot honestly accuse them of racism, or bigotry.
Why I Left Islam, By Dr Ali Sina
Dr Sina:
"I vehemently reject any recognition of Islam as a legitimate religion and call for its total denunciation and ban. If seventy years ago someone called for total denunciation of Nazism, he probably would have been called an extremist, yet a decade later everyone adopted that view. Should we not learn from history? Evil must be rejected completely and without reservation."-Dr Ali Sina:
"The penalty of apostasy in Islam is death. Here is my own testimony.":
http://www.faithfreedom.org/Articles/sina/why_i_left_islam.htm
Ex-Muslim testimonial book by Ibn Warraq:
Testimonials by ex-Muslims about leaving Islam
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