Iran's social structure like a pendulum

Iran's social structure is like a pendulum. It was sitting stable in the middle, until the forces that be put the Shah in power, and in effect pulled the pendulum to one side. The Islamic Revolution in effect is the pendulum swung to another side. Through various repititions of swinging back and forth through time will Iran's pendulum return back to the middle. I believe a US invasion would be like a hand giving the pendulum another shove, and making the swinging keep on longer.

However, using the pendulum analogy, a hand could come and stop the pendulum. But what would that hand be in real life?