Also, they are silent because they know better than most of us that Islam is not a "peaceful" religion. It is a faith that spread slavery, intolerance and violence wherever it goes. Non-Muslim minorities in every Muslim country have been the objects of persecution and Muslims minorities in other countries have always been in the forefront of terrorist anti-government activities.
In doing so, they are only following the inhjunctions of the Mad Prophet himself. Read the Koran and the Hadiths and be enlighted about "true" Islam, unbelievers!
Shoot, all you have to do is read the first 9 chapters of the Koran. That'll be enough.