Political Islam and the Middle East's Revolutions

Since the 1979 Iranian revolution and hostage crisis, political Islam from the point of view of many Western powers is known with the label "threat". After the events of September 11 global struggle began against political Islam camp. Thus, political Islam in the twenty-first century replaced with communism in the Cold War.
But the beginning of presidency of Barack Obama and his efforts to realize the motto of "change”, the necessity of change the power's balance in the Middle East and Moscow's warning strategy in South Ossetia War that indicated a resurgence of Russian threats, all caused the United States strategy to be revised toward political Islam. The result of the revision was revealed in the "Arab Spring".

It was clear that the Arabic revolutions in many countries such as Tunisia, Egypt, Yemen and etc. have accompanied by Islamic thoughts and charter. Thus, it was predictable that political Islam emerged as a result of the "Arab Spring" and escalated across the Middle East.
United States position regarding political Islam became apparent when it did nothing to halt the series of revolutions. While, during the Cold War, Washington cooperating with the CIA tried to break the dominoes of left-wing politics and communism in Latin America. Coups in Guatemala, Brazil and Chile are examples of these efforts. 
Apart from Bahrain, why, despite the concerns of Tel Aviv and Riyadh, nothing actual and practical happened to stop these revolutions?!