IICC Report, March 16, 2009.

According to international laws governing of armed conflict, mosques
used for military purposes lose the special protection afforded houses of
worship and may become legitimate targets for attack.

1. Operation Cast Lead illustrated the varied military uses made by Hamas of
   the mosques under its control in the Gaza Strip. During the operation evidence
   (which was extensively documented by the Intelligence and Terrorism
   Information Center) was found about the storage of weapons in mosques
   (rockets, IEDs, light arms and even an anti-aircraft gun), and about using the
   mosques for military training and as bases from which to launch rockets into
   Israel and mortar shells at IDF forces nearby.
2. The extensive use made of mosques by terrorist organizations and radical
   Islamic groups for military, terrorist and political purposes is not limited to the
   Gaza Strip. This study also examines similar uses made by Hamas in Judea and
   Samaria, Hezbollah in south Lebanon, and global jihad and other radical Islamic
   groups in various countries around the Arab-Muslim world (in conflict focal
   points such as Iraq and Pakistan) and even in the Muslim communities in
   Europe.In many locations both in the Middle East and beyond, radical Islamic
   terrorist organizations exploit the mosques to hide weapons, organize in
   preparation for attacks, enlist supporters and terrorist operatives, preach
   terrorism and indoctrinate Muslims who come to worship with hatred for Israel,
   the Jewish people, the West in general and the United States in particular, as
   well as for pro-Western Arab and Islamic regimes.
3. The study also examines the religious and social roots of the use of mosques
   for military and political purposes. Senior Islamic clerics, both Sunni and Shi’ite
   (particularly the Sunni sheikh Yussuf Qardawi and the Shi’ite Ayatollah
   Khamenei), repeatedly claim that making such use of the mosques for jihad
   objectives is legitimate according to Islamic point of view. They also encourage
   their use for spreading jihad ideology and terrorism (muqawamah, i.e.,
   “resistance”) against the enemies of Islam. Their religious views are based on
   the Islamic oral traditions (hadiths) which say that the prophet Muhammad
   himself used a mosque for military and political purposes, beyond the classic
   use of the mosque as house of worship.
4. The use made by terrorist organizations of mosques for military purposes and
   as launching pads for terrorist attacks is liable to endanger innocent civilians
   who have no link to the organizations. It harms the status and special
   protection afforded houses of worship by international laws of armed combat,
   as well as the protection afforded civilian structures and the civilian population
   in general. The laws of armed conflict unequivocally state that houses of
   worship used for military purposes lose their right to protection and thus expose
   themselves to attack.Hamas and Islamic terrorist groups claim that attacking mosques (even
   though they were put to military-terrorist purposes) is illegal and is an
   infringement of the freedom of worship. Those claims, aimed primarily at
   Western ears where public opinion regards the mosques as places used
   exclusively for religious purposes, are worthless. The measures taken by the
   IDF in the Gaza Strip against mosques used for military purposes, as well as
   those taken by other countries, including, for example, the United States in
   Iraq, were in accordance with international law and arose from the natural
   commitment of any state to defend its citizens .
5. The legitimate battle against the military and political use made of mosques
   by terrorist organizations and radical Islamic elements has been waged in
   various ways: during Operation Cast Lead in the Gaza Strip, the IDF attacked
   mosques used for such purposes by Hamas; in Iraq, the United States attacked
   mosques in Fallujah and other cities because they were being used as military
   bases by insurgents and other terrorist elements; in Judea and Samaria the
   Palestinian Authority invaded mosques controlled by Hamas and confiscated
   weapons and propaganda materials, and detained clerics; in Pakistan the regime
   was forced to take over the entire Red Mosque precinct in Islamabad, where
   radical Islamic activities were being held and from which terrorist groups
   affiliated with the global jihad launched their attacks.
6. Arab countries such as Saudi Arabia have been forced to impose close
   security supervision on the mosques which are home to global jihad groups
   whose activities are also directed against the host countries (the sheikh of
   Al-Azhar mosque, Muhammad Al-Tantawi, who is a senior religious authority in
   the Sunni Muslim world, determined that a country has the full right to attack a
   mosque to preserve its security interests). In addition, European countries
   (especially Britain) and the United States were also forced to impose close
   security supervision on mosques which had become focal points for global jihad
   incitement and terrorist activities, especially after September 11, 2001 .
7. The radical Islamist terrorist exploitation of mosques for military and political
   purposes can be expected to continue. The struggle against such exploitation
   has met several serious difficulties, especially since in many places Islamic
   terrorist organizations enjoy great popularity with those who come to the
   mosques (popularity which is sometimes greater than that of the countries and
   regimes fighting terrorism, each in its own way). Nevertheless, the struggle
   must be continued in a variety of ways as an integral part of the global war
   against terrorism and its various manifestations.

See full IICC report (pdf).