Please let us remember, those that commit these atrocities are totally evil wankers and they may say they are doing something in the name of Allah, but as 99% of all Muslims would concur, Allah has nothing whatsoever to do with this. There are evil people from every religion, nation, and walk of life. There always has been and there always will be, but did we, for example, take vengeance on the Icelandic people as they descended for the Arian stock the Nazis considered superior for the horrificcrimes of the Third Reich? No, and just as we do not target blond haired blue eyed people, neither should we target mosques and Muslims.
Lets not stoop to the same level as these evil bastards, but resist evil and strive to be better in the face of it. Use a little cold logic to temper the hot vengeance.