Because their islamic societies are backward and they lack the resources to engang in full scale jihad.
And don't forget the are too busy oppressing a large bulk of their own populations too.
Ever hear of Turkey? Malaysia?
Most Muslim nations which are now experiencing social upheaval were either conquered and created by Western powers (most Arab nations, Indonesia, most African Muslim populations) or are supported by Wahhibists (Kosovo, Bosnia, Chechnya).
The problem is not Islam. It is a mix of fundamentalism and oppression.