Why do few Muslims to condemn the vio_ence and intolerance of fellow Muslims?

The vast majority of Muslims, it is said, want peace. But some have shaken this world with their vio_ence and intolerance. Yet few Muslims - as far as I know - dared to criticize or condemn the behavior of the violent and radical few. Is this inability or failure of many Muslims to condemn such actions of their co-religionists be cause for alarm? Germans kept silent about the Fuhrer (first name: Adolf) in the years leading to World War II. Whatever happened to right reason and fairness? Do Muslims tolerate bad behavior of fellow Muslims?