The mainstream media is not going to be able to avoid mentioning Islam in connection with this story.
However, I expect they will adopt the strategy of playing up the Chechen nationalism angle in order to overshadow talk of global jihad.
With the Chechen nationalism angle they can make the Chechens out to be victims, and maybe even find a way to work in a few shots at George W. Bush.
The party line I've discerned from MSNBC and CNN is:
What would drive two young American men to do something so terrible to people they know so well? We may never be able to answer this question.