In the current tensions with the Islamic World, pundits bandy about received wisdom that in fact is often ignorance. Here are a few examples.
1) The solution of radical Islam must come from within Islam.
Perhaps it could. It would be nice to see the advice of General Sisi of Egypt take root among the Islamic street. It would have been nice had the Arab Spring resulted in constitutional republics from North Africa to Syria. It would be nice if an all-Muslim force took on and defeated the Islamic State. It would be nice if Iran suddenly stopped stonings and Saudi Arabia ceased public whippings. It would be nice if Muslims dropped the death penalty for apostates.
Unfortunately, there is no reason to believe that any of these scenarios is soon likely.